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<article article-type="case-report" dtd-version="1.1" specific-use="sps-1.9" xml:lang="en" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">
	<front>
		<journal-meta>
			<journal-id journal-id-type="publisher-id">ABC HF</journal-id>
			<journal-title-group>
				<journal-title>ABC: Heart Failure &amp; Cardiomyopathy</journal-title>
				<abbrev-journal-title abbrev-type="publisher">ABC Heart Fail Cardiomyop</abbrev-journal-title>
			</journal-title-group>
			<issn pub-type="epub">2764-3107</issn>
			<publisher>
				<publisher-name>Sociedade Brasileira de Cardiologia - SBC</publisher-name>
			</publisher>
		</journal-meta>
		<article-meta>
			<article-id pub-id-type="publisher-id">abchf.20220047</article-id>
			<article-id pub-id-type="doi">10.36660/abchf.20220047</article-id>
			<article-categories>
				<subj-group subj-group-type="heading">
					<subject>Case Report</subject>
				</subj-group>
			</article-categories>
			<title-group>
				<article-title>Incessant Malignant Ventricular Arrhythmia in a Patient with Advanced Heart Failure: A Case Report</article-title>
			</title-group>
			<contrib-group>
				<contrib contrib-type="author">
					<contrib-id contrib-id-type="orcid">0000-0001-8667-5276</contrib-id>
					<name>
						<surname>Murad</surname>
						<given-names>Ciro Mancilha</given-names>
					</name>
					<xref ref-type="aff" rid="aff1"><sup>1</sup></xref>
					<xref ref-type="corresp" rid="c1"/>
				</contrib>
				<contrib contrib-type="author">
					<name>
						<surname>de Campos</surname>
						<given-names>Iáscara Wozniak</given-names>
					</name>
					<xref ref-type="aff" rid="aff1"><sup>1</sup></xref>
				</contrib>
				<aff id="aff1">
					<label>1</label>
					<institution content-type="orgname">Universidade de São Paulo</institution>
					<institution content-type="orgdiv1">Faculdade de Medicina</institution>
					<institution content-type="orgdiv2">Hospital das Clínicas</institution>
					<addr-line>
						<named-content content-type="city">São Paulo</named-content>
						<named-content content-type="state">SP</named-content>
					</addr-line>
					<country country="BR">Brazil</country>
					<institution content-type="original">Instituto do Coração (InCor), Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP – Brazil</institution>
				</aff>
			</contrib-group>
			<author-notes>
				<corresp id="c1"><bold>Mailing Address: Ciro Mancilha Murad</bold> • Núcleo de Transplantes – Instituto do Coração (InCor) – Av. Dr. Enéas Carvalho de Aguiar, 44. Postal Code <postal-code>05403-900</postal-code>, Cerqueira César, São Paulo, SP – Brazil, E-mail: <email>ciromurad@hotmail.com</email>
				</corresp>
				<fn fn-type="con">
					<p><bold>Author Contributions</bold></p>
					<p>Writing of the manuscript and Critical revision of the manuscript for intellectual content: Murad CM e Campos IW.</p>
				</fn>
				<fn fn-type="conflict">
					<p><bold>Potential Conflict of Interest</bold></p>
					<p>No potential conflict of interest relevant to this article was reported.</p>
				</fn>
			</author-notes>
			<pub-date date-type="pub" publication-format="electronic">
				<day>29</day>
				<month>06</month>
				<year>2022</year>
			</pub-date>
			<pub-date date-type="collection" publication-format="electronic">
				<season>Apr-Jun</season>
				<year>2022</year>
			</pub-date>
			<volume>2</volume>
			<issue>2</issue>
			<fpage>232</fpage>
			<lpage>233</lpage>
			<history>
				<date date-type="received">
					<day>25</day>
					<month>03</month>
					<year>2022</year>
				</date>
				<date date-type="rev-recd">
					<day>13</day>
					<month>04</month>
					<year>2022</year>
				</date>
				<date date-type="accepted">
					<day>03</day>
					<month>05</month>
					<year>2022</year>
				</date>
			</history>
			<permissions>
				<license license-type="open-access" xlink:href="https://creativecommons.org/licenses/by/4.0/" xml:lang="en">
					<license-p>This is an open-access article distributed under the terms of the Creative Commons Attribution License</license-p>
				</license>
			</permissions>
			<kwd-group xml:lang="en">
				<title>Keywords</title>
				<kwd>Heart Failure</kwd>
				<kwd>Intra-Aortic Balloon Pumping</kwd>
				<kwd>Tachycardia, Ventricular</kwd>
			</kwd-group>
			<counts>
				<fig-count count="0"/>
				<table-count count="0"/>
				<equation-count count="0"/>
				<ref-count count="8"/>
				<page-count count="2"/>
			</counts>
		</article-meta>
	</front>
	<body>
		<sec sec-type="intro">
			<title>Introduction</title>
			<p>The occurrence of refractory ventricular arrhythmia in patients with heart failure (HF) is a therapeutic dilemma.<sup><xref ref-type="bibr" rid="B1">1</xref></sup> These patients, especially in the presence of advanced disease, may experience multiple triggering factors for ventricular arrhythmia, such as myocardial fibrosis, ischemia, hydroelectrolytic disorders, ventricular distention, the arrhythmogenic potential of drugs, and the underlying disease itself.<sup><xref ref-type="bibr" rid="B1">1</xref>–<xref ref-type="bibr" rid="B3">3</xref></sup> Conversely, sustained ventricular arrhythmias cause hemodynamic compromise, resulting in further ischemia and ventricular distension.<sup><xref ref-type="bibr" rid="B1">1</xref></sup> This can lead to a vicious cycle of hemodynamic worsening with an increasingly arrhythmogenic myocardium.<sup><xref ref-type="bibr" rid="B1">1</xref></sup> Usual treatment consists of direct current (DC) cardioversion, antiarrhythmic drugs, myocardial revascularization (when indicated), and catheter ablation. However, invasive procedures are always considered high risk in such cases. We report the case of a patient with incessant ventricular arrhythmia resistant to several types of treatment.</p>
		</sec>
		<sec sec-type="cases">
			<title>Case Report</title>
			<p>A 53-year-old male patient was transferred to our hospital due to an episode of sustained ventricular tachycardia (VT) that had occurred 48 hours earlier and was initially treated in other hospital. The patient had been on the heart transplant waiting list for 2 years due to the presence of idiopathic dilated cardiomyopathy with a left ventricular ejection fraction (LVEF) of 26%. He underwent VT ablation 5 years ago and cardiac resynchronization therapy (CRT) device implantation 3 years ago. There was also a history of chronic atrial fibrillation (anticoagulated), hypertension, depression, and hypothyroidism. Before the event, the patient was in New York Heart Association (NYHA) functional class II. Immediately after admission, he had another episode of sustained VT with hemodynamic instability and underwent DC cardioversion. After the episode, the patient developed signs of low cardiac output and was started on dobutamine, sodium nitroprusside, and intravenous amiodarone. Electronic evaluation of the CRT device showed several episodes of sustained VT in the last 24 hours. Hydroelectrolytic disorders were also recognized and immediately corrected. Increased free T4 (2.04 ng/dL, reference value: 0.89-1.76 ng/dL) and normal thyrotropin levels were also identified. Amiodarone-induced thyroiditis was suspected and empirical treatment with corticosteroids was started. However, a new episode of sustained VT requiring DC cardioversion occurred in the next morning. During the afternoon, the patient had an episode of cardiac arrest with polymorphic VT rhythm (<italic>torsades de pointes</italic>) and underwent electrical defibrillation. Electrocardiogram showed a prolonged QT interval, thus the infused dobutamine dose was reduced and amiodarone infusion was changed to lidocaine. The patient had another episode of sustained VT requiring DC cardioversion on the following day, and amiodarone infusion was subsequently reinstated. An episode of supraventricular tachycardia occurred on the same day and rapidly progressed to acute pulmonary edema. Due to refractory ventricular arrhythmias and acute decompensated HF, the patient underwent intra-aortic balloon pumping (IABP) implantation on the following day (day 4 of hospitalization). After IABP, the patient was weaned off dobutamine and there was no recurrence of ventricular arrhythmias. However, the patient developed nosocomial pneumonia and required antibiotic therapy for 14 days (piperacillin-tazobactam, meropenem, and teicoplanin). Because the patient was dependent on mechanical circulatory support and the possibility of further VT ablation was excluded, his status on the transplant waiting list was reactivated and updated to urgent. On day 63 after IABP without arrhythmia recurrence, the patient underwent a heart transplant.</p>
		</sec>
		<sec sec-type="discussion">
			<title>Discussion</title>
			<p>The case described here shows the multifactorial mechanism of ventricular arrhythmia genesis in a patient with advanced HF. In addition to the arrhythmogenic substrate (idiopathic dilated cardiomyopathy which needed previous ablation), hydroelectrolytic disorders and amiodarone-induced thyroidopathy may have contributed to the onset of the condition. This leads to the vicious cycle of hemodynamic deterioration with perpetuation of the arrhythmic condition. The difficulty in clinical management is also evident: inotropic agents have the potential for hemodynamic stabilization at the expense of a proarrhythmic effect. Conversely, the occurrence of <italic>torsades de pointes</italic> due to QT prolongation exemplifies a known fact that antiarrhythmic agents may also cause proarrhythmic effects, although by different mechanisms. This issue was resolved by using mechanical circulatory support through IABP for hemodynamic stabilization and ventricular arrhythmia control. IABP also allowed for dobutamine weaning, resulting in the removal of a proarrhythmic factor.</p>
			<p>Some case reports and series describing the use of IABP with the primary objective of controlling ventricular arrhythmias have been published.<sup><xref ref-type="bibr" rid="B1">1</xref>,<xref ref-type="bibr" rid="B4">4</xref>–<xref ref-type="bibr" rid="B7">7</xref></sup> In one of the first cases described, IABP was able to control ventricular arrhythmias in the setting of post-infarction in a patient who received more than 120 electrical cardioversions.<sup><xref ref-type="bibr" rid="B7">7</xref></sup> Other reports have also demonstrated the use of IABP for refractory ventricular arrhythmia control in patients without coronary artery disease.<sup><xref ref-type="bibr" rid="B1">1</xref>,<xref ref-type="bibr" rid="B4">4</xref>,<xref ref-type="bibr" rid="B6">6</xref></sup> In a case series of 12 patients, IABP was effective in controlling ventricular arrhythmias in 18 cases.<sup><xref ref-type="bibr" rid="B1">1</xref></sup> Of these, 5 underwent a heart transplant, 12 became stable and were weaned off IAB support, and 3 were refractory to IABP.<sup><xref ref-type="bibr" rid="B1">1</xref></sup> One patient was diagnosed with cardiac amyloidosis and associated systemic involvement and was considered unsuitable for transplantation.<sup><xref ref-type="bibr" rid="B1">1</xref></sup> In this study, coronary artery disease (acute and chronic) was evident in 18 of 21 patients and all had ventricular dysfunction, with a mean LVEF of 29%.<sup><xref ref-type="bibr" rid="B1">1</xref></sup> Nineteen patients were discharged from hospital and followed up for 25.7 months, with a survival rate of 95%.<sup><xref ref-type="bibr" rid="B1">1</xref></sup></p>
			<p>Several mechanisms have been proposed to explain how IABP helps to control ventricular arrhythmias.<sup><xref ref-type="bibr" rid="B1">1</xref>,<xref ref-type="bibr" rid="B5">5</xref></sup> The primary mechanism is the increase in coronary perfusion by active insufflation during diastole, which may reduce ischemia as a precipitating factor in ventricular arrhythmia genesis.<sup><xref ref-type="bibr" rid="B5">5</xref></sup> However, IABP may also be effective in patients with no evidence of coronary artery disease.<sup><xref ref-type="bibr" rid="B4">4</xref>,<xref ref-type="bibr" rid="B6">6</xref></sup> In such cases, the support provided by IABP may allow sufficient time for anti-arrhythmic drugs to work and interrupt the vicious cycle of hemodynamic deterioration and arrhythmogenesis.<sup><xref ref-type="bibr" rid="B1">1</xref></sup> Finally, dilation and increased tension in the left ventricular wall have been shown to cause electrophysiological changes in the myocardium, creating an arrhythmogenic substrate.<sup><xref ref-type="bibr" rid="B1">1</xref>,<xref ref-type="bibr" rid="B3">3</xref>,<xref ref-type="bibr" rid="B8">8</xref></sup> This may be a particularly important mechanism in patients with advanced HF. In this case, IABP acts directly by reducing ventricular afterload, consequently decreasing tension in the left ventricular wall.<sup><xref ref-type="bibr" rid="B1">1</xref>,<xref ref-type="bibr" rid="B5">5</xref></sup></p>
			<p>The case described here emphasizes the complexity of managing incessant ventricular arrhythmias in a patient with advanced HF. It also shows the role of IABP in hemodynamic stabilization, interruption of the cycle of progressive arrhythmogenesis, and as a bridge to heart transplantation.</p>
		</sec>
	</body>
	<back>
		<fn-group>
			<fn fn-type="supported-by" id="fn1">
				<p><bold>Sources of Funding</bold></p>
				<p>There were no external funding sources for this study.</p>
			</fn>
			<fn fn-type="other" id="fn2">
				<p><bold>Study Association</bold></p>
				<p>This study is not associated with any thesis or dissertation work.</p>
			</fn>
			<fn fn-type="other" id="fn3">
				<p><bold>Ethics approval and consent to participate</bold></p>
				<p>This article does not contain any studies with human participants or animals performed by any of the authors.</p>
			</fn>
		</fn-group>
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			</ref>
		</ref-list>
	</back>
	<sub-article article-type="translation" id="S01" xml:lang="pt">
		<front-stub>
			<article-categories>
				<subj-group subj-group-type="heading">
					<subject>Relato de Caso</subject>
				</subj-group>
			</article-categories>
			<title-group>
				<article-title>Arritmia Ventricular Maligna Incessante em Paciente com Insuficiência Cardíaca Avançada: Um Relato de Caso</article-title>
			</title-group>
			<contrib-group>
				<contrib contrib-type="author">
					<contrib-id contrib-id-type="orcid">0000-0001-8667-5276</contrib-id>
					<name>
						<surname>Murad</surname>
						<given-names>Ciro Mancilha</given-names>
					</name>
					<xref ref-type="aff" rid="aff2"><sup>1</sup></xref>
					<xref ref-type="corresp" rid="c2"/>
				</contrib>
				<contrib contrib-type="author">
					<name>
						<surname>de Campos</surname>
						<given-names>Iáscara Wozniak</given-names>
					</name>
					<xref ref-type="aff" rid="aff2"><sup>1</sup></xref>
				</contrib>
				<aff id="aff2">
					<label>1</label>
					<addr-line>
						<named-content content-type="city">São Paulo</named-content>
						<named-content content-type="state">SP</named-content>
					</addr-line>
					<country country="BR">Brasil</country>
					<institution content-type="original">Instituto do Coração (InCor), Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP – Brasil</institution>
				</aff>
			</contrib-group>
			<author-notes>
				<corresp id="c2"><bold>Correspondência: Ciro Mancilha Murad</bold> • Núcleo de Transplantes - Instituto do Coração (InCor) – Av. Dr. Enéas Carvalho de Aguiar, 44. CEP <postal-code>05403-900</postal-code>, Cerqueira César, São Paulo, SP – Brasil, E-mail: <email>ciromurad@hotmail.com</email>
				</corresp>
				<fn fn-type="con">
					<p><bold>Contribuição dos autores</bold></p>
					<p>Redação do manuscrito e Revisão crítica do manuscrito quanto ao conteúdo intelectual importante: Murad CM e Campos IW.</p>
				</fn>
				<fn fn-type="conflict">
					<p><bold>Potencial conflito de interesse</bold></p>
					<p>Não há conflito com o presente artigo</p>
				</fn>
			</author-notes>
			<kwd-group xml:lang="pt">
				<title>Palavras-chave</title>
				<kwd>Insuficiência Cardíaca</kwd>
				<kwd>Balão Intra-Aórtico</kwd>
				<kwd>Taquicardia Ventricular</kwd>
			</kwd-group>
		</front-stub>
		<body>
			<sec sec-type="intro">
				<title>Introdução</title>
				<p>Em portadores de insuficiência cardíaca (IC), a ocorrência de arritmia ventricular refratária representa um dilema terapêutico.<sup><xref ref-type="bibr" rid="B1">1</xref></sup> Esses pacientes, particularmente na vigência de doença avançada, podem apresentar múltiplos fatores desencadeadores de arritmia ventricular: fibrose miocárdica, isquemia, distúrbios hidroeletrolíticos, distensão ventricular, potencial arritmogênico de drogas e a própria doença de base.<sup><xref ref-type="bibr" rid="B1">1</xref>–<xref ref-type="bibr" rid="B3">3</xref></sup> Por outro lado, arritmias ventriculares sustentadas causam comprometimento hemodinâmico, gerando mais isquemia e distensão ventricular.<sup><xref ref-type="bibr" rid="B1">1</xref></sup> Dessa forma, pode-se instalar um ciclo vicioso de piora hemodinâmica e um miocárdio cada vez mais arritmogênico.<sup><xref ref-type="bibr" rid="B1">1</xref></sup> O tratamento habitual consiste em cardioversão elétrica sincronizada (CVE), medicação antiarrítmica, revascularização miocárdica quando indicada e ablação por cateter; todavia, nessas circunstâncias, procedimentos invasivos são sempre de alto risco. Aqui, relatamos o caso de um paciente com arritmia ventricular incessante refratária a várias linhas de tratamento.</p>
			</sec>
			<sec sec-type="cases">
				<title>Relato de caso</title>
				<p>Trata-se de um paciente de 53 anos, do sexo masculino, transferido para nosso serviço devido a um episódio de taquicardia ventricular (TV) sustentada ocorrida há 48 h e atendida inicialmente em outro hospital. Portador de miocardiopatia dilatada idiopática com fração de ejeção do ventrículo esquerdo (FEVE) de 26%, já estava ativo em fila de transplante cardíaco pelo nosso serviço há 2 anos. Foi submetido a ablação de TV há 5 anos e implante de marca-passo ressincronizador há 3 anos. Também tem história de fibrilação atrial crônica (anticoagulado), hipertensão arterial sistêmica, depressão e hipotireoidismo. Antes do evento, estava em classe funcional II da New York Heart Association (NYHA). Logo após a admissão em nosso serviço, apresentou novo episódio de TV sustentada com instabilidade hemodinâmica, sendo submetido a CVE. Após o episódio, evoluiu com sinais de baixo débito cardíaco, sendo necessário início de dobutamina, nitroprussiato de sódio e impregnação endovenosa de amiodarona. Foi realizada avaliação eletrônica do marca-passo, que identificou diversos episódios de TV sustentada nas últimas 24 h. Na ocasião, também foram identificados distúrbios hidroeletrolíticos, logo corrigidos. Foi evidenciada, ainda, elevação de T4 livre (2,04 ng/dL [valor de referência 0,89-1,76 ng/dL]), com níveis de hormônio estimulador da tireoide (TSH) normais, sendo suspeitada tireoidite induzida por amiodarona e iniciado tratamento empírico com corticoide. Todavia, na manhã seguinte, houve um novo episódio de TV sustentada com necessidade de CVE. Durante a tarde, apresentou um episódio de parada cardiorrespiratória (PCR) em ritmo de TV polimórfica (<italic>torsades de pointes</italic>) e foi submetido a desfibrilação elétrica. Identificou-se prolongamento do intervalo QT no eletrocardiograma, sendo reduzida dose de infusão de dobutamina e trocada infusão de amiodarona por lidocaína. No dia seguinte, apresentou novo episódio de TV sustentada com necessidade de CVE, e, posteriormente, foi reiniciada infusão de amiodarona. No mesmo dia, apresentou um episódio de taquicardia supraventricular, evoluindo rapidamente com edema agudo de pulmão. No dia seguinte (quarto dia de internação), devido ao quadro de arritmias ventriculares refratárias e descompensação grave de IC, optou-se pela passagem de balão intra-aórtico (BIA). Após a passagem de BIA, foi realizado desmame de dobutamina, e não houve recorrência de arritmias ventriculares. O paciente apresentou episódio de pneumonia nosocomial, com necessidade de tratamento com antibióticos por 14 dias (piperacilina-tazobactam, meropenem e teicoplanina). Posteriormente, devido à dependência de suporte circulatório mecânico e esgotadas possibilidades de novas ablações de TV, foi reativado em fila de transplante com critério de urgência. Após 63 dias do implante do BIA, sem recorrência de arritmias, foi submetido ao transplante cardíaco.</p>
			</sec>
			<sec sec-type="discussion">
				<title>Discussão</title>
				<p>O caso descrito exemplifica o mecanismo multifatorial da gênese de arritmias ventriculares em portadores de IC avançada. Além do substrato arritmogênico – miocardiopatia dilatada idiopática com necessidade de ablação prévia – distúrbios hidroeletrolíticos e tireoidopatia induzida por amiodarona podem ter contribuído para deflagração do quadro. Posteriormente, inicia-se o ciclo vicioso de deterioração hemodinâmica e perpetuação do quadro arrítmico. Também fica evidente a dificuldade de manejo clínico: agentes inotrópicos têm potencial de estabilização hemodinâmica à custa de efeito pró-arrítmico. Por outro lado, a ocorrência de <italic>torsades de pointes</italic> por prolongamento de QT exemplifica um fato já conhecido: que mesmo agentes antiarrítmicos podem ter efeitos pró-arrítmicos, por mecanismos distintos. A solução encontrada foi utilização de suporte circulatório mecânico, através do BIA para estabilização hemodinâmica e controle das arritmias ventriculares. Neste caso, o uso do BIA também permitiu o completo desmame de dobutamina, retirando, assim, um fator pró-arrítmico.</p>
				<p>Alguns relatos e séries de casos já foram publicados descrevendo a utilização do BIA com objetivo primário de controle de arritmias ventriculares.<sup><xref ref-type="bibr" rid="B1">1</xref>,<xref ref-type="bibr" rid="B4">4</xref>–<xref ref-type="bibr" rid="B7">7</xref></sup> Em um dos primeiros casos descritos, o BIA foi eficaz para controle de arritmias ventriculares no contexto pós-infarto, em um paciente que havia recebido mais de 120 CVEs.<sup><xref ref-type="bibr" rid="B7">7</xref></sup> Outros relatos também demonstraram o uso de BIA para controle de arritmias ventriculares refratárias em pacientes sem doença coronariana.<sup><xref ref-type="bibr" rid="B1">1</xref>,<xref ref-type="bibr" rid="B4">4</xref>,<xref ref-type="bibr" rid="B6">6</xref></sup> Em uma série de casos de 21 pacientes, o BIA foi eficaz para controle de arritmias ventriculares em 18 casos.<sup><xref ref-type="bibr" rid="B1">1</xref></sup> Destes, 5 foram submetidos a transplante cardíaco, 12 foram estabilizados e foi retirado o suporte com BIA e 3 foram refratários ao uso do BIA.<sup><xref ref-type="bibr" rid="B1">1</xref></sup> Um paciente foi diagnosticado com amiloidose cardíaca com envolvimento sistêmico, não sendo considerado apto para transplante.<sup><xref ref-type="bibr" rid="B1">1</xref></sup> Nessa série, 18 dos 21 pacientes tinham evidência de doença arterial coronariana (aguda ou crônica), e todos os pacientes tinham disfunção ventricular (FEVE média de 29%).<sup><xref ref-type="bibr" rid="B1">1</xref></sup> Dezenove pacientes receberam alta hospitalar e foram seguidos por 25,7 meses, com sobrevida de 95%.<sup><xref ref-type="bibr" rid="B1">1</xref></sup></p>
				<p>Uma série de mecanismos já foram propostos para explicar a maneira como o BIA age no controle de arritmias ventriculares.<sup><xref ref-type="bibr" rid="B1">1</xref>,<xref ref-type="bibr" rid="B5">5</xref></sup> O mecanismo primário de funcionamento do BIA é o aumento da perfusão coronariana através da insuflação ativa na diástole, o que pode reduzir a isquemia como um fator precipitante na gênese de arritmias ventriculares.<sup><xref ref-type="bibr" rid="B5">5</xref></sup> Todavia, o BIA pode ser eficaz mesmo em pacientes sem evidência de doença coronariana.<sup><xref ref-type="bibr" rid="B4">4</xref>,<xref ref-type="bibr" rid="B6">6</xref></sup> Nesses casos, é possível que o suporte oferecido pelo BIA dê tempo para o funcionamento de drogas antiarrítmicas e interrompa o ciclo vicioso de deterioração hemodinâmica e arritmogênese.<sup><xref ref-type="bibr" rid="B1">1</xref></sup> Por fim, já foi demonstrado que dilatação e aumento da tensão na parede ventricular esquerda altera propriedades eletrofisiológicas do miocárdio, criando substrato arritmogênico.<sup><xref ref-type="bibr" rid="B1">1</xref>,<xref ref-type="bibr" rid="B3">3</xref>,<xref ref-type="bibr" rid="B8">8</xref></sup> Esse pode ser um mecanismo particularmente importante em pacientes com IC avançada. Nesses casos, o BIA age diretamente através da redução de pós-carga ventricular e consequentemente reduz a tensão na parede ventricular esquerda.<sup><xref ref-type="bibr" rid="B1">1</xref>,<xref ref-type="bibr" rid="B5">5</xref></sup></p>
				<p>O caso descrito enfatiza a complexidade do manejo de arritmia ventriculares incessantes em paciente com IC avançada. Demonstra, ainda, o papel do BIA na estabilização hemodinâmica, na interrupção do ciclo de arritmogênese progressiva e no uso como ponte para transplante cardíaco.</p>
			</sec>
		</body>
		<back>
			<fn-group>
				<fn fn-type="supported-by" id="fn4">
					<p><bold>Fontes de financiamento</bold></p>
					<p>O presente estudo não teve fontes de financiamento externas.</p>
				</fn>
				<fn fn-type="other" id="fn5">
					<p><bold>Vinculação acadêmica</bold></p>
					<p>Não há vinculação deste estudo a programas de pós-graduação.</p>
				</fn>
				<fn fn-type="other" id="fn6">
					<p><bold>Aprovação ética e consentimento informado</bold></p>
					<p>Este artigo não contém estudos com humanos ou animais realizados por nenhum dos autores.</p>
				</fn>
			</fn-group>
		</back>
	</sub-article>
</article>