Ischemia – ABC CARDIOL

ABC

Original Article

Comparison of Coronary Computed Tomography Angiography and Invasive Coronary Angiography in Nonobstructive Coronary Artery Disease: The Brazilian Coronary ARtery Disease (BARD) Study

Protásio Lemos Da Luz et al. Desiderio Favarato Alexandre A. Abizaid Luiz Antonio Machado César … Carlos Vicente Serrano Antônio Carlos Palandri Chagas Carlos E. Rochitte Marco A. Gutierrez

Abstract

Background

The prognosis of nonobstructive coronary artery disease (CAD) is not well established. Comparative data between coronary computed tomography angiography (CCTA) and invasive coronary angiography (ICA) are limited.

Objectives

To compare CCTA- and ICA-derived information in nonobstructive CAD regarding detection and clinical outcomes.

Methods

We followed 4,004 adult patients who underwent either ICA (n = 2,355) or CCTA (n = 1,649) for a median of 9 years. The primary endpoint was a composite of all-cause mortality, acute coronary syndrome/acute myocardial infarction, and stroke. Propensity score matching was performed to compare outcomes between groups. The significance level was set at 5%.

Results

The overall event rate was 6.9%. ICA was associated with worse outcomes than CCTA (hazard ratio [HR] 0.54; 95% CI 0.42-0.68; p < 0.001). Patients with nonobstructive CAD had worse outcomes than those without CAD (HR 1.73; 95% CI 1.32-2.27; p < 0.001). Normal coronary findings on CCTA were associated with better outcomes than normal findings on ICA (HR 0.39; 95% CI 0.24-0.62; p < 0.001). Event rates increased proportionally with plaque burden. In 1,187 matched pairs, CCTA was associated with improved survival (HR 0.57; 95% CI 0.42-0.78; p < 0.001).

Conclusion

CCTA more closely reflects clinical outcomes than ICA. Nonobstructive CAD carries a substantial risk regardless of imaging modality.

Read Full Article

ABCIC

Review Article

Assessment of Myocardial Ischemia with the Integrated Use of Multimodality Imaging

Thiago Nunes Pereira Leite et al. Luís Henrique Wolff Gowdak

Abstract

Myocardial ischemia, which is characterized by reduced oxygen supply to the myocardium, is a common manifestation of coronary artery disease (CAD), one of the leading causes of morbidity and mortality worldwide. Early and accurate detection of myocardial ischemia is essential for risk stratification, treatment planning, and improved clinical outcomes. In recent years, advances in cardiac imaging modalities have provided a more comprehensive assessment of myocardial ischemia. This article reviews recent advances in the assessment and detection of myocardial ischemia with a focus on the integrated use of multimodality imaging. The article discusses the main techniques available, their advantages and limitations, and their role in current clinical practice, in addition to future perspectives in this area. Cardiac imaging modalities for assessment of myocardial ischemia include exercise electrocardiography, stress echocardiography, single-photon emission computed tomography, positron emission tomography, cardiac magnetic resonance imaging, and coronary computed tomography angiography. When selected imaging tests, it is necessary to consider the pre-test probability (PTP) of CAD and patients’ clinical characteristics. Non-invasive functional modalities are preferable for patients with intermediate probability of CAD. The integration of these modalities can improve sensitivity, specificity, and diagnostic accuracy, offering a more complete assessment of the patient’s cardiovascular condition and allowing for more personalized therapeutic planning.

In conclusion, the multimodal approach to myocardial ischemia assessment improves early detection, risk stratification, and therapeutic planning. The combination of several imaging modalities allows a holistic view of the cardiovascular condition, improving diagnostic accuracy and clinical outcomes in patients with suspected or established diagnosis of CAD.

Read Full Article

ABC

Original Article

The Relationship between the Systemic Immune-Inflammation Index and Ischemia with Non-Obstructive Coronary Arteries in Patients Undergoing Coronary Angiography

Muammer Karakayali et al. Mehmet Altunova Turab Yakisan Serkan Aslan … Timor Omar Inanc Artac Doğan Ilis Ayca Arslan Zihni Cagin Yavuz Karabag Ibrahim Rencuzogullari

Abstract

Background:

Ischemia with the non-obstructive coronary artery (INOCA) is an ischemic heart disease that mostly includes coronary microvascular dysfunction and/or epicardial coronary vasospasm due to underlying coronary vascular dysfunction and can be seen more commonly in female patients. The systemic immune-inflammation index (SII, platelet × neutrophil/lymphocyte ratio) is a new marker that predicts adverse clinical outcomes in coronary artery disease (CAD).

Objective:

This study aims to investigate the relationship between INOCA and SII, a new marker associated with inflammation.

Methods:

A total of 424 patients (212 patients with INOCA and 212 normal controls) were included in the study. Peripheral venous blood samples were received from the entire study population prior to coronary angiography to measure SII and other hematological parameters. In our study, the value of p<0.05’ was considered statistically significant.

Results:

The optimal cut-off value of SII for predicting INOCA was 153.8 with a sensitivity of 44.8% and a specificity of 78.77% (Area under the curve [AUC]: 0.651 [95% CI: 0.603–0.696, p=0.0265]). Their ROC curves were compared to assess whether SII had an additional predictive value over components. The AUC value of SII was found to be significantly higher than that of lymphocyte (AUC: 0.607 [95% CI: 0.559–0.654, p = 0.0273]), neutrophil (AUC: 0.559 [95%CI: 0.511–0.607, p=0.028]) and platelet (AUC: 0.590 [95% CI: 0.541–0.637, p = 0.0276]) in INOCA patients.

Conclusions:

A high SII level was found to be independently associated with the existence of INOCA. The SII value can be used as an indicator to add to the traditional expensive methods commonly used in INOCA prediction.

Read Full Article

ABC

Letter to the Editor

Invasive Versus Conservative Management of NSTEMI Patients Aged ≥ 75 Years: Commentary

Sérgio Renato da Rosa Decker et al. Luiza Duarte Pittol Regis Goulart Rosa Marciane Maria Rover

Dear Editor,

In the edition of Arquivos Brasileiros de Cardiologia, Mengjin Hu et al. evaluated the benefit of early invasive strategy for elderly patients with non-ST-elevation myocardial infarction (NSTEMI), concluding that this strategy yields positive results in reducing myocardial infarction, major adverse cardiac events, and urgent revascularization outcomes. However, we have concerns regarding the authors’ claim of superiority and the relevance of the chosen outcomes for this specific population. Firstly, these outcomes (ischemia-driven outcomes) are mostly surrogate endpoints based on troponin levels. To establish the surrogacy of one outcome to another, several factors need to be considered, including biological plausibility, associations in observational studies, and, most importantly, proof of concept through trials where improving the surrogate endpoint also enhances clinical outcomes. In this sense, evidence shows that the association between nonfatal myocardial infarction and all-cause or cardiovascular mortality meets the first two levels; however, a meta-analysis of randomized clinical trials did not establish nonfatal myocardial infarction as a surrogate for all-cause or cardiovascular mortality. Indeed, this is a reproducible relationship in short and long term outcomes; the metanalysis of FRISC-II, ICTUS, and RITA-3 showed that, after five years, early invasive strategy for patients with NSTEMI did not result in reduced mortality despite the benefits seen in ischemia-driven outcomes.

[…]

Read Full Article

ABC

Original Article

Prognostic Assessment of Fractional Flow Reserve in Different Strata in Patients with Coronary Artery Disease

Denise Pellegrini et al. Paulo R. A. Caramori Ricardo Czarnobai Soccol Ricardo Lasevitch … Gustavo Luís Agostini Alice Dussin Flavio Vinicius Costa Ferreira Mario Bernardes Wagner Luiz Carlos Bodanese

Abstract

Background

There are limited real-world data on the clinical course of untreated coronary lesions according to their functional severity.

Objective

To evaluate the 5-year clinical outcomes of patients with revascularized lesions with fractional flow reserve (FFR) ≤ 0.8 and patients with non-revascularized lesions with FFR > 0.8.

Methods

The FFR assessment was performed in 218 patients followed for up to 5 years. Participants were classified based on FFR into ischemia group (≤ 0.8, intervention group, n = 55), low-normal FFR group (> 0.8-0.9, n = 91), and high-normal FFR group (> 0.9, n = 72). The primary endpoint was major adverse cardiac events (MACEs), a composite of death, myocardial infarction, and need for repeat revascularization. The significance level was set at 0.05; therefore, results with a p-value < 0.05 were considered statistically significant.

Results

Most patients were male (62.8%) with a mean age of 64.1 years. Diabetes was present in 27%. On coronary angiography, the severity of stenosis was 62% in the ischemia group, 56.4% in the low-normal FFR group, and 54.3% in the high-normal FFR group (p<0.05). Mean follow-up was 3.5 years. The incidence of MACEs was 25.5%, 13.2%, and 11.1%, respectively (p=0.037). MACE incidence did not differ significantly between the low-normal and high-normal FFR groups.

Conclusion

Patients with FFR indicative of ischemia had poorer outcomes than those in non-ischemia groups. There was no difference in the incidence of events between the low-normal and high-normal FFR groups. Long-term studies with a large sample size are needed to better assess cardiovascular outcomes in patients with moderate coronary stenosis with FFR values between 0.8 and 1.0.

Read Full Article

ABC

Original Article

Coronary Tortuosity as a New Phenotype for Ischemia without Coronary Artery Disease

André Estrada et al. André Silveira Sousa Claudio Tinoco Mesquita Humberto Villacorta

Abstract

Background

Coronary arteries tend to be more tortuous than other arteries and follow the repeated flexion and relaxation movements that occur during the cardiac cycle. Coronary tortuosity (CorT) leads to changes in coronary flow with a reduction in distal perfusion pressure, which could cause myocardial ischemia.

Objective

To assess the association between CorT and myocardial ischemia.

Methods

Between January 2015 and December 2017, 57 patients with angina and nonobstructive coronary artery disease detected by invasive coronary angiography (ICA) were retrospectively enrolled. Angiographic variables were analyzed to assess the presence and degree of tortuosity and correlated with their respective vascular territories on stress myocardial perfusion imaging (MPI). CorT was defined as coronary arteries with three or more bend angles ≤90°, measured during diastole. Statistical significance was determined at the 5% level.

Results

A total of 17 men and 40 women were enrolled (mean age 58.3 years). CorT was observed in 16 patients (28%) and in 24 of 171 arteries. There was a significant association between CorT and ischemia when analyzed per artery (p<0.0001). The angiographic factor most associated with ischemia was the number of bend angles in an epicardial artery measured at systole (p=0.021).

Conclusion

This study showed an association of CorT and myocardial ischemia in patients with unobstructed coronary arteries and angina. An increased number of coronary bend angles measured by angiography during systole was related to ischemia.

Read Full Article

ABCIC

Brief Communication

Evaluation of Functional Risk Area by Myocardial Strain Analysis in Unstable Angina

Pedro Henrique Albuquerque et al. José Maria Del Castillo Luciano Borba Carlos Romério Ferro … Cyro Cabral Júnior Antônio Everaldo Filho Ricardo César Cavalcanti

[…]

Read Full Article

ABCIC

Case Report

Agenesia of Right Pulmonary Artery Associated with High Output Coronary Fistula for Superior Vena Cava and Intrapulmonary Artery Branches: Case Report

Aline Valério de Lima et al. Stella Souza Carneiro José Augusto Murad José Ayrton Arruda … José Guilherme Caselli Edson Egashira

[…]

Read Full Article

ABC

Clinicoradiological Correlation

Case 2/2020 – Anomalous Origin of the Left Coronary Artery from the Pulmonary Trunk, Under Natural Evolution in a 75-Year-old Asymptomatic Woman

Edmar Atik et al. Oliver Kligerman Luiz Kajita

Clinical data

Patient evolves without symptoms in her daily routine as a domestic worker. She denies any symptoms of palpitations, precordial pain or fatigue. When she was aged 62, a cardiac catheterization revealed the diagnosis of anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA, or Bland-White-Garland syndrome), after an altered routine exercise stress test. Since then, the patient reports her well-being, although she is aware of the existence of this anomaly. She is being treated with rosuvastatin, levothyroxine and vitamin D.

Physical examination: good overall status, eupneic, acyanotic, normal pulses in the four limbs. Weight: 49.8 Kg, Height: 143 cm, BP:120 x 80 mmHg, HR: 74 bpm.

[…]

Read Full Article

ABC

Editorial

The Role of Sympathetic System as a Therapeutic Option in the Ischemia/Reperfusion Injury

Bertha F. Polegato et al. Leonardo A. M. Zornoff

Coronary artery disease is the leading cause of mortality and the most resource-consuming health pathology in industrialized countries. In the United States, it is believed that more than 12 million individuals have ischemic heart disease.

It is estimated that approximately 1 million cases of acute coronary syndrome occur annually in the United States, demonstrating that this syndrome occurs in epidemic proportions. Few pathologies have evolved as radically as AMI, with a marked reduction in mortality as a result of changes in treatment over the past 30 years, particularly cardiac reperfusion.^,

[…]

Read Full Article

ABC

Original Article

Acute Physical Stress Preconditions the Heart Against Ischemia/Reperfusion Injury Through Activation of Sympathetic Nervous System

Alireza Imani et al. Hoda Parsa Leila Gholami Chookalaei Kamran Rakhshan … Masoomeh Golnazari Mahdieh Faghihi

Abstract

Background:

Stress is defined as a complicated state that related to homeostasis disturbances, over-activity of the sympathetic nervous system and hypothalamus-pituitary-adrenal axis responses. Cardiac preconditioning reduces myocardial damages.

Objective:

This study was designed to assess the cardioprotective effects of acute physical stress against ischemia/reperfusion (I/R) injury through the activation of the sympathetic nervous system.

Methods:

Thirty-two male Wistar rats were divided into four groups; (1) IR (n = 8): rats underwent I/R, (2) Acute stress (St+IR) (n = 8): physical stress induced 1-hour before I/R, (3) Sympathectomy (Symp+IR) (n = 8): chemical sympathectomy was done 24-hours before I/R and (4) Sympathectomy- physical stress (Symp+St+IR) (n = 8): chemical sympathectomy induced before physical stress and I/R. Chemical sympathectomy was performed using 6-hydroxydopamine (100 mg/kg, sc). Then, the hearts isolated and located in the Langendorff apparatus to induce 30 minutes ischemia followed by 120 minutes reperfusion. The coronary flows, hemodynamic parameters, infarct size, corticosterone level in serum were investigated. P < 0.05 demonstrated significance.

Results:

Physical stress prior to I/R could improve left ventricular developed pressure (LVDP) and rate product pressure (RPP) of the heart respectively, (63 ± 2 versus 42 ± 1.2, p < 0.05, 70 ± 2 versus 43 ± 2.6, p < 0.05) and reduces infarct size (22.16 ± 1.3 versus 32 ± 1.4, p < 0.05) when compared with the I/R alone. Chemical sympathectomy before physical stress eliminated the protective effect of physical stress on I/R-induced cardiac damages (RPP: 21 ± 6.6 versus 63 ± 2, p < 0.01) (LVDP: 38 ± 4.5 versus 43 ± 2.6, p < 0.01) (infarct size: 35 ± 3.1 versus 22.16 ± 1.3, p < 0.01).

Conclusion:

Findings indicate that acute physical stress can act as a preconditional stimulator and probably, the presence of sympathetic nervous system is necessary.

Read Full Article

ABC

Original Article

Whole-Body Vibration Training Increases Myocardial Salvage Against Acute Ischemia in Adult Male Rats

Shahnaz Shekarforoush et al. Mohammad Reza Naghii

Abstract

Background:

Whole body vibration training (WBV) is a new training program, which is safe and effective. It can be followed by the public. However, data on the safety and efficacy of vibration on myocardial ischemia reperfusion (IR) injury are lacking.

Objective:

To examine the effect of WBV on the tolerance of the myocardium to acute IR injury in an experimental rat model.

Methods:

Twenty-four male Wistar rats were divided into control and vibration groups. Vibration training consisted of vertical sinusoidal whole body vibration for 30 min per day, 6 days per week, for 1 or 3 weeks (WBV1 and WBV3 groups, respectively). All the rats were submitted to myocardial IR injury. Myocardial infarct size and ischemia-induced arrhythmias were assessed. Differences between variables were considered significant when p < 0.05.

Results:

No differences were observed between the groups regarding the baseline hemodynamic parameters. Infarct size was smaller in the experimental group (control, 47 ± 2%; WBV1, 39 ± 2%; WBV3, 37 ± 2%; p < 0.05, vs. control). Vibration produced a significant decrease in the number and duration of ventricular tachycardia (VT) episodes compared to the control value. All ventricular fibrillation (VF) episodes in the vibration groups were self-limited, while 33% of the rats in the control group died due to irreversible VF (p = 0.02).

Conclusion:

The data showed that vibration training significantly increased cardiac tolerance to IR injury in rats, as evidenced by reduction in the infarct size and cardiac arrhythmias, and by facilitating spontaneous defibrillation.

Read Full Article

ABC

Original Article

Effects of Nitrate Intake on Myocardial Ischemia-Reperfusion Injury in Diabetic Rats

Sajad Jeddi et al. Saeedeh Khalifi Mahboubeh Ghanbari Fatemeh Bageripour Asghar Ghasemi

Abstract

Background:

Coronary artery disease is 2-3 times more common in diabetic individuals. Dietary nitrate/nitrite has beneficial effects in both diabetes and cardiovascular disease. It also has protective effects against myocardial ischemia-reperfusion (IR) injury in healthy animals. However, the effects of nitrate on myocardial IR injury in diabetic rats have not yet been investigated.

Objective:

We examined the effects of dietary nitrate on myocardial IR injury in streptozotocin-nicotinamide-induced diabetic rats.

Method:

Rats were divided into four groups (n=7 in each group): control, control+nitrate, diabetes, and diabetes+nitrate. Type 2 diabetes was induced by injection of streptozotocin and nicotinamide. Nitrate (sodium nitrate) was added to drinking water (100 mg/L) for 2 months. The hearts were perfused in a Langendorff apparatus at 2 months and assessed before (baseline) and after myocardial IR for the following parameters: left ventricular developed pressure (LVDP), minimum and maximum rates of pressure change in the left ventricle (±dP/dt), endothelial nitric oxide (NO) synthase (eNOS) and inducible NO synthase (iNOS) mRNA expression, and levels of malondialdehyde (MDA) and NO metabolites (NOx).

Results:

Recovery of LVDP and ±dP/dt was lower in diabetic rats versus controls, but almost normalized after nitrate intake. Diabetic rats had lower eNOS and higher iNOS expression both at baseline and after IR, and dietary nitrate restored these parameters to normal values after IR. Compared with controls, heart NOx level was lower in diabetic rats at baseline but was higher after IR. Diabetic rats had higher MDA levels both at baseline and after IR, which along with heart NOx levels decreased following nitrate intake.

Conclusion:

Dietary nitrate in diabetic rats provides cardioprotection against IR injury by regulating eNOS and iNOS expression and inhibiting lipid peroxidation in the heart.

Read Full Article

ABC

Original Article

Is Local Nitric Oxide Availability Responsible for Myocardial Salvage after Remote Preconditioning?

Esbeidira Aranet Arroyo-Martínez et al. Alejandra Meaney Gabriela Gutiérrez-Salmeán Juan Miguel Rivera-Capello … Vidal González-Coronado Alejandro Alcocer-Chauvet Genaro Castillo Nayelli Nájera Guillermo Ceballos Eduardo Meaney

Abstract

Background:

Remote ischemic preconditioning (RIPC) represents an attractive therapy for myocardial protection, particularly when ischemic events can be anticipated. Although several hypothetic mechanisms have been proposed, no definite molecular pathways have been elucidated.

Objective:

We evaluated the effect of brachial circulation cuff occlusion on myocardial ischemic tolerance, necrosis, and nitric oxide (NO) in patients with ischemic heart disease undergoing elective percutaneous coronary interventions (PCI).

Methods:

46 patients were randomly allocated into two groups: control and RIPC before PCI procedures. Electrocardiographic analysis, serum concentrations of troponin I (cTn-I) were measured at baseline and 24 hours after PCI. A blood sample from the atherosclerotic plaque was drawn to determine nitrate and nitrites.

Results:

RIPC increased the availability of NO in the stented coronary artery. Control patients presented a small but significant increase in cTn-I, whilst it remained unchanged in preconditioned group. The preconditioning maneuver not only preserved but also enhanced the sum of R waves.

Conclusions:

RIPC induced an intracoronary increase of NO levels associated with a decrease in myocardial damage (measured as no increase in cTn-I) with electrocardiographic increases in the sum of R waves, suggesting an improved myocardium after elective PCI.

Read Full Article

ABC

Original Article

Serial High-Sensitivity Troponin T in Post-Primary Angioplasty Exercise Test

Humberto Andres Vaz et al. Ana Paula Vanz Iran Castro

Abstract

Background:

The kinetics of high-sensitivity troponin T (hscTnT) release should be studied in different situations, including functional tests with transient ischemic abnormalities.

Objective:

To evaluate the release of hscTnT by serial measurements after exercise testing (ET), and to correlate hscTnT elevations with abnormalities suggestive of ischemia.

Methods:

Patients with acute ST-segment elevation myocardial infarction (STEMI) undergoing primary angioplasty were referred for ET 3 months after infarction. Blood samples were collected to measure basal hscTnT immediately before (TnT_0h), 2 (TnT_2h), 5 (TnT_5h), and 8 hours (TnT_8h) after ET. The outcomes were peak hscTnT, TnT_5h/TnT_0h ratio, and the area under the blood concentration-time curve (AUC) for hscTnT levels. Log-transformation was performed on hscTnT values, and comparisons were assessed with the geometric mean ratio, along with their 95% confidence intervals. Statistical significance was assessed by analysis of covariance with no adjustment, and then, adjusted for TnT_0h, age and sex, followed by additional variables (metabolic equivalents, maximum heart rate achieved, anterior wall STEMI, and creatinine clearance).

Results:

This study included 95 patients. The highest geometric means were observed at 5 hours (TnT_5h). After adjustments, peak hscTnT, TnT_5h/TnT_0h and AUC were 59% (p = 0.002), 59% (p = 0.003) and 45% (p = 0.003) higher, respectively, in patients with an abnormal ET as compared to those with normal tests.

Conclusion:

Higher elevations of hscTnT may occur after an abnormal ET as compared to a normal ET in patients with STEMI.

Read Full Article

ABC

Original Article

Myocardial Scintigraphy in the Evaluation of Cardiac Events in Patients without Typical Symptoms

Paola Emanuela Poggio Smanio et al. Juliana Horie Silva João Vitor Holtz Leandro Ueda … Marilia Abreu Carlindo Marques Leonardo Machado

Abstract

Background:

Cardiovascular disease is a leading cause of death in the world and in Brazil. Myocardial scintigraphy is an important noninvasive method for detecting ischemia in symptomatic patients, but its use in asymptomatic ones or those with atypical symptoms is yet to be defined.

Objective:

To verify the presence of major cardiac events in asymptomatic patients or those with atypical symptoms (atypical chest pain or dyspnea) that underwent myocardial scintigraphy (MS), over a period of 8 years. Secondary objectives were to identify cardiac risk factors associated with myocardial scintigraphy abnormalities and possible predictors for major cardiac events in this group.

Methods:

This was a retrospective, observational study using the medical records of 892 patients that underwent myocardial scintigraphy between 2005 and 2011 and who were followed until 2013 for assessment of major cardiac events and risk factors associated with myocardial scintigraphy abnormalities. Statistical analysis was performed by Fisher’s exact test, logistic regression and Kaplan-Meyer survival curves, with statistical significance being set at p ≤ 0.05.

Results:

Of the total sample, 52.1% were men, 86.9% were hypertensive, 72.4% had hyperlipidemia, 33.6% were diabetic, and 12.2% were smokers; 44.5% had known coronary artery disease; and 70% had high Framingham score, 21.8% had moderate and 8% had low risk. Of the myocardial scintigraphies, 58.6% were normal, 26.1% suggestive of fibrosis and 15.3% suggestive of ischemia. At evolution, 13 patients (1.5%) had non-fatal myocardial infarction and six individuals (0.7%) died. The group with normal myocardial scintigraphy showed longer period of time free of major cardiac events, non-fatal myocardial infarction (p = 0.036) and death. Fibrosis in the myocardial scintigraphy determined a 2.4-fold increased risk of non-fatal myocardial infarction and five-fold higher risk of death (odds ratio: 2.4 and 5.7, respectively; p = 0.043).

Conclusion:

The occurrence of major cardiac events in 8 years was small. Patients with fibrosis at MS had more major events, whereas patients with normal MS result had fewer major cardiac events, with higher survival.

Read Full Article

ABC

Artigo Original

Effects of angiotensin-I and ischemia on functional recovery in isolated hearts

Ubirajara Oliveira de Oliveira et al. Álvaro Reischak de Oliveira Luiz Carlos Kucharski Ubiratan Fabres Machado … Maria Claudia Irigoyen Beatriz D'Agord Schaan

BACKGROUND: Cardiac arrest resuscitation can present myocardial dysfunction determined by ischemic time, and inhibition of the angiotensin-converting enzyme (ACE) can reduce cardiac dysfunction during reperfusion. OBJECTIVE: To investigate the effects of angiotensin-I and different periods of ischemia on functional recovery in isolated rat hearts. METHODS: Isolated hearts from Wistar rats (n=45; 250-300 g) were submitted to different periods of global ischemia (20, 25 or 30 min) and reperfused (30 min) with Krebs-Henseleit buffer alone or with the addition of 400 nmol/L angiotensin-I, or 400 nmol/L angiotensin-I + 100 mmol/L captopril along the reperfusion period. RESULTS: The maximal positive derivative of pressure (+dP/dt max) and rate-pressure product were reduced in hearts exposed to 25 min ischemia (~73%) and 30 min ischemia (~80%) vs. 20 min ischemia. Left ventricular end-diastolic pressure (LVEDP) and perfusion pressure (PP) were increased in hearts exposed to 25 min ischemia (5.5 and 1.08 fold, respectively) and 30 min ischemia (6 and 1.10 fold, respectively) vs. 20 min ischemia. Angiotensin-I caused a decrease in +dP/dt max and rate-pressure product (~85-94%) in all ischemic periods and an increase in LVEDP and PP (6.9 and 1.25 fold, respectively) only at 20 min ischemia. Captopril was able to partially or completely reverse the effects of angiotensin-I on functional recovery in 20 min and 25 min ischemia. CONCLUSION: These data suggest that angiotensin-II directly or indirectly participates in the post-ischemic damage, and the ability of an ACE inhibitor to attenuate this damage depends on ischemic time.

Read Full Article

ABC

Artigo Original

Silent myocardial ischemia in patients with stable coronary artery disease receiving conventional antianginal drug therapy

João Fernando Monteiro Ferreira et al. Luiz Antonio Machado César César J. Gruppi Dante M. A. Giorgi … Whady A. Hueb Antonio P. Mansur José A. F. Ramires

BACKGROUND: Few data are available on the behavior of myocardial ischemia during daily activities in patients with coronary artery disease receiving antianginal drug therapy. OBJECTIVE: To study the mechanism generating myocardial ischemia by evaluating blood pressure and heart rate changes in patients with stable atherosclerotic disease receiving drug therapy and with evidence of myocardial ischemia. METHODS: Fifty non-hospitalized patients (40 males) underwent 24-hour electrocardiographic monitoring synchronized with blood pressured monitoring. RESULTS: Thirty five episodes of myocardial ischemia were detected in 17 patients, with a total duration of 146.3 minutes; angina was reported in five cases. Twenty nine episodes (100.3 minutes) occurred during wakefulness, with 11 episodes (35.3 + 3.7 min) in the period from 11 a.m. to 3 p.m. Blood pressure and heart rate evaluation in the three ten-minute intervals following the ischemic episodes showed a statistically significant difference (p< 0.05), unlike that shown for the three intervals preceding the episodes. However, during the ischemic episode, a higher than 10-mmHg elevation in blood pressure and 5 beats per minute in heart rate were observed when compared with the time interval between 20 and 10 minutes before the episode. The mean heart rate at the onset of ischemia during the exercise test performed before the study was 118.2 + 14.0, and 81.1 + 20.8 beats per minute on the 24-hour electrocardiogram (p < 0.001). CONCLUSION: The incidence of silent myocardial ischemia is high in stable coronary artery disease and is related to alterations in blood pressure and heart rate, with different thresholds for ischemia for the same patient.

Read Full Article

ABC

Artigo Original

Sustained improvement in symptoms and exercise capacity up to six months after autologous transendocardial transplantation of bone marrow mononuclear cells in patients with severe ischemic heart disease

Hans Fernando R. Dohmann et al. Emerson C. Perin Radovan Borojevic Suzana A. Silva … Andre L. S. Souza Guilherme V. Silva João A. R. Assad Maria I. D. Rossi Claudio T. Mesquita Hans J. Dohmann

OBJECTIVE: This study aimed at assessing the effects of autologous transendocardial transplantation of bone marrow mononuclear cells (ATTBMMC) on symptoms, exercise capacity, myocardial perfusion and contractility in patients with severe ischemic heart disease during a 6-month follow-up period. METHODS: This prospective study comprised 21 patients as follows: the first 14 patients forming the treated group, and the last 7 patients forming the control group. Initially, all patients underwent clinical and laboratory assessment, treadmill testing, echocardiography, myocardial scintigraphy, and 24-hour Holter. The bone marrow mononuclear cells (BMMC) were isolated, washed, and diluted in 0.9% saline solution for transendocardial injection in areas of viable myocardium in the treated group, (15 0.2-mL injections). All patients were reassessed in the end of 2 and 6 months of follow-up. RESULTS: The demographic data and other characteristics did not significantly differ between the groups in the initial evaluation. No major adverse events related to the ATTBMMC were observed. In the end of 6 months, a reduction in the ischemic area was observed on nuclear perfusion imaging (P=0.05), as was a significant improvement in symptoms, functional capacity, and left ventricular overall function. CONCLUSION: This study showed that transendocardial injections of BMMC are safe in human beings with ischemic heart disease associated with severe ventricular dysfunction. The effects observed in the short run were maintained up to the sixth month of follow-up.

Read Full Article

ABC

Original Article

Surgical myocardial revascularization without extracorporeal circulation

Salomón Soriano Ordinola Rojas et al. Viviane C. Veiga Januario M. Souza Marcos S. Berlinck … José Alberto Iasbech Luiz Alberto Magna Reinaldo W. Vieira Sergio A. Oliveira

OBJECTIVE: To assess the immediate postoperative period of patients undergoing myocardial revascularization without extracorporeal circulation with different types of grafts. METHODS: One hundred and twelve patients, 89 (79.5%) of whom were males, were revascularized without extracorporeal circulation. Their ages ranged from 39 to 85 years. The criteria for indicating myocardial revascularization without extracorporeal circulation were as follows: revascularized coronary artery caliber > 1.5 mm, lack of intramyocardial trajectory on coronary angiography, noncalcified coronary arteries, and tolerance of the heart to the different rotation maneuvers. RESULTS: Myocardial revascularization without extracorporeal circulation was performed in 112 patients. Three were converted to extracorporeal circulation, which required a longer hospital stay but did not impact mortality. During the procedure, the following events were observed: atrial fibrillation in 10 patients, ventricular fibrillation in 4, total transient atrioventricular block in 2, ventricular extrasystoles in 58, use of a device to retrieve red blood cells in 53, blood transfusion in 8, and arterial hypotension in 89 patients. Coronary angiography was performed in 20 patients on the seventh postoperative day when the grafts were patent. CONCLUSION: Myocardial revascularization without extracorporeal circulation is a reproducible technique that is an alternative for treating ischemic heart disease.

Read Full Article

ABC

Original Article

Effects of chlorthalidone and diltiazem on myocardial ischemia in elderly patients with hypertension and coronary artery disease

João Batista Serro-Azul et al. Rogério Silva de Paula César Gruppi Lígia Pinto … Humberto Pierri Amit Nussbacher Otávio Gebara Paulo Moffa Antônio Carlos Pereira-Barreto Maurício Wajngarten

OBJETIVE: Antihypertensive therapy with thiazides decreases coronary events in elderly patients. However, the influence of diuretics on myocardial ischemia has not been fully investigated. The aim of this study was to compare the effect of chlorthalidone and diltiazem on myocardial ischemia. METHODS: Following a randomized, double-blind, crossover protocol, we studied 15 elderly hypertensive patients aged 73.6±4.6 years with myocardial ischemia. All patients had angiographically documented coronary artery disease. We measured patients using 48- hour ambulatory electrocardiogram monitoring and exercise testing. After a 2-week period using placebo, patients received chlorthalidone or diltiazem for 4 weeks. RESULTS: Both treatments lowered systolic and diastolic blood pressures. The number of ischemic episodes on ambulatory electrocardiogram recordings was reduced with the use of chlorthalidone (2.5±3.8) and diltiazem (3.2±4.2) when compared with placebo (7.9±8.8; p<0.05). The total duration of ischemic episodes was reduced in both treatments when compared with placebo (chlorthalidone: 19.2±31.9min; diltiazem: 19.3±29.6min; placebo: 46.1±55.3min; p<0.05). CONCLUSION: In elderly hypertensive patients with coronary artery disease, chlorthalidone reduced myocardial ischemia similarly to diltiazem. This result is consistent with epidemiological studies and suggests that reduction of arterial blood pressure with thiazide therapy plays an important role in decreasing myocardial ischemia.

Read Full Article