Resource-constrained settings comprise areas with limited diagnostic and management facilities due to access, financial scarcity, or political unwillingness, irrespective of the urban/rural setting.

Two types of resource constraints were put forward: resource constraints for HCPs (infrastructure, investigation tool, tests, echocardiogram [ECHO] machines, training, lack of storage facilities for special drugs) and resource constraints for patients (affordability, inaccessibility).

There is a noticeable disparity between the availability and use of infrastructure, which can be attributed to the general public's ignorance of diseases, which causes them to seek medical attention only after the illness has advanced significantly and reached a complex stage, making treatment more difficult.

Despite multiple health insurance schemes from government and private providers, its uptake in the population is low due to a lack of willingness and acceptability to pay the premiums and limited coverage of specific needs, particularly for elderly patients with disabilities and chronic diseases.

There is an urgent need to train more general practitioners in a rural settings, seeking support from the government to improve facilities offered in resource-constrained settings.

There is an increased trend of chronic diseases among the younger population and children due to changes in food habits, sedentary lifestyles, increased screen time, obesity, hypertension, chronic kidney disease, dyslipidemia, and metabolic syndrome.³⁴ The disability-adjusted life years (DALYs) due to non-communicable diseases (NCDs) increased from 30% in 1990 to 55% in 2016.³⁵

Experts have noted that the genetics of the population is one of the contributing risk factors for the increase in the incidence of developing CAD.

Southern state governments provide free or low-cost common medication for chronic diseases. Despite this, patients often discontinue the regimen upon experiencing short-term improvements, risking harm, increased mortality, and higher treatment costs.

Low-cost and easily available spurious drugs are yet another challenge in the resource-constrained settings of India. The intake of these drugs leads to serious health issues due to their substandard quality.

Infrastructure-related: The nonavailability of diagnostic tests (electrocardiogram [ECG], treadmill test [TMT], two-dimensional echocardiogram [2D-ECHO]), medications, and increased dependence on the private sector are the major challenges faced in diagnosing CCS. However, few experts have noted that as per the ESC guidelines, ECHO is not essential for every patient and may increase stress on the already-stressed infrastructure.

HCP-related: It was discovered that HCPs in the peripheral setup were unaware of the difference between CAD and CCS. Acute coronary syndrome (ACS) and CCS have unusual presentations; hence, it was determined that continuing medical education sessions and AI-based applications would be essential in educating HCPs, primary care physicians, and paramedical staff about CCS. The growing need for improved communication channels between the HCPs in the peripheries and specialists in urban areas was emphasized. This could be facilitated through standard risk questionnaires and detailed case record maintenance. Experts have noted that ischemia and myocardial infarction with no obstructive CAD are commonly reported in patients with migraine or vascular diseases and perimenopausal females, which leads to significant morbidity if left untreated and poses great challenges in diagnosis, even for the experienced clinician.

Patient-related: Poverty in resource-constrained settings has promoted quackery and faith in quacks among patients. The loss of many patients with chronic disease to alternative therapies was reported to be disastrous in the long run. Furthermore, social media platforms were reported to spread false information about the disease. Comorbidities such as anemia, chronic obstructive pulmonary disease, thyroid functions, and diabetes lead to adverse outcomes in patients with CCS and predispose them to the conversion of CCS to ACS, which requires intervention and higher treatment modality with additional cost (Table 1).

Table 1

Challenges	Solutions
Lack of awareness	Obtaining endorsements from well-known personalities, propagating awareness via mass media, distributing booklets and pamphlets with awareness material in regional languages, and projecting awareness messages on television in the OPD Initiating a “know your number” (blood pressure, blood glucose, and cholesterol — strong indicators of CVDs) campaign across the settings to make people aware of their health status and take charge, recognize undiagnosed and uncontrolled patients, and take necessary management action Organizing patient and HCP education programs
Lifestyle	Lifestyle modifications right from childhood by updating the curriculum along with the involvement/guidance of pediatricians
Advanced/ alternative avenues	Telemedicine applications through tie-ups with the nearest medical college Creating an algorithm for the diagnosis and management of CCS in resource-constrained settings (Figure 2)
Public-private partnership	Early prevention policy by public-private partnerships (government, pharmaceutical companies) specifically charted for a resource-constrained setting Proposing a norm for HCPs to render services in resource-constrained settings by providing them with incentives Providing incentives to patients to ensure adequate follow-up Conducting mass screening camps by HCPs with public-private partnerships and village panchayats to provide minimum investigation tools and cost-effective medications in resource-constrained settings

CCS: Chronic coronary syndrome; CVD: Cardiovascular disease; HCP: Health care professional; OPD: Outpatient department. Source: Author

The experts noted that thorough history taking followed by simple diagnostic tests are necessary first steps in the diagnosis of CCS. The ECG and ECHO were minimum requirements in the health centers.

Male patients and those with comorbidities were advised to undergo TMT for a regular assessment; patients with a moderate or high likelihood of disease should be considered for invasive angiography, while those with a low or intermediate probability should be considered for CT angiography.

Lifestyle modification and pharmacotherapy (DAPT) were emphasized for preventing complications and further cardiac events. The expert opinions are summarized further in Table 2.

Table 2

Challenges	Solutions
Screening/diagnosis	Clinical history/examination A thorough clinical history should be taken Simple tests such as physical BP monitoring, finger prick for glucose monitoring, biomarker testing, and perfusion scans should be performed to increase the likelihood of a definite diagnosis Noninvasive test ECG and ECHO should be considered as the bare minimum requirement, and calcium scoring should be considered for identifying patients with obstructive CAD with a high likelihood TMTs for male patients and patients with diabetes should be routinely considered in fitness programs to provide functional capacity CT angiography should be considered only in the low and intermediate probability of disease Invasive tests Invasive angiography should be considered in those with moderate or high likelihood of disease
Management	Lifestyle modification A healthy diet, physical exercise, and good hygiene practices remain the first steps to be taken against CCS Pharmacotherapy Use of nitrates for symptomatic relief and delay the onset of complications Dual pathway inhibitors and dual platelets were reported to be less effective, and the use of a combination of antiplatelets and anticoagulants was emphasized. A fixed-dose combination of atorvastatin and ezetimibe was also noted to be beneficial among Indian patients Others Creating a checklist with rigid preset criteria comprising one hemodynamic agent, one metabolic agent, and symptomatic treatment Allocating separate resources for ACS and CCS

ACS: Acute coronary syndrome; BP: Blood pressure; CAD: Coronary artery disease; CCS: Chronic coronary system; CT: computed tomography; ECHO: Echocardiogram; ECG: Electrocardiogram; TMT: treadmill test. Source: Author

The experts proposed an algorithm that would aid in the diagnosis and management of CCS in resource-constrained settings (Figure 2).

Figure 2 Source: Author.

The OPTA approach was approved for use in such settings. The use of the OPTA checklist and combination drug therapy in patients with CCS was stressed.

The development of a native language OPTA questionnaire for outpatient use was suggested to ensure optimal treatment for chronic stable angina.

Digital technology, including sharing ECG readings via cloud/instant messaging, electronic intensive care units for remote monitoring, and AI for diagnosis of CCS, can significantly impact patient diagnosis and management.

Considering the expert opinions and extensive literature search, an algorithm has been proposed for CCS management. It involves detailed history, clinical examination, noninvasive/invasive tests, telehealth confirmation from a cardiologist, lifestyle modification aided by ASHA workers, pharmacotherapy tailored to comorbidities, and timely revascularization referrals. Furthermore, patient management is categorized based on risk severity: the low-risk emphasizing lifestyle modification, intermediate-risk combining lifestyle management and pharmacotherapy, and high-risk situations prioritizing revascularization (Central Illustration).