Benefícios da Terapêutica de Ressincronização Cardíaca na «Miocardiopatia Muito Dilatada»

INTRODUCTION: Recent clinical trials have studied parameters that could predict response to cardiac resynchronization therapy (CRT) in patients with advanced heart failure. Left ventricular end-diastolic dimension (LVEDD) is regarded as a possible predictor of response to CRT. OBJECTIVE: To study the response to CRT in patients with very dilated cardiomyopathy, i.e. those at a more advanced stage of the pathology, analyzing both the responder rate and reverse remodeling in two groups of patients classified according to LVEDD. METHODS: We performed a retrospective analysis of 71 patients who underwent CRT (aged 62 +/- 11 years; 65% male; 93% in NYHA functional class > or = III; 31% with ischemic cardiomyopathy; left ventricular ejection fraction [LVEF] 25.6 +/- 6.8%; 32% in atrial fibrillation; QRS 176 +/- 31 ms). Twenty-two (31%) patients with LVEDD > or = 45 mm/m2 (49.2 +/- 3.5 mm/m2) were considered to have very dilated cardiomyopathy (Group A) and 49 patients had LVEDD > 37 mm/m2 and < 45 mm/m2 (39.4 +/- 3.8 mm/m2) (Group B). All patients were assessed by two-dimensional echocardiography at baseline and six months after CRT. The following parameters were analyzed: NYHA functional class, LVEF and LVEDD. Responders were defined clinically (improvement of > or = 1 NYHA class) and by echocardiography, with a minimum 15% increase over baseline LVEF combined with a reduction in LVEDD (reverse remodeling). RESULTS: There were no significant differences in baseline demographic characteristics between the two groups. At six-month followup, we observed an improvement in LVEF (delta 8.5 +/- 11.8%) and a reduction in LVEDD (delta 3.7 +/- 6.8 mm/m2), with fifty-seven (79%) patients being classified as clinical responders. The percentage of patients with reverse remodeling was similar in both groups (64% vs. 73%, p = NS), as were percentages of improved LVEF (delta 6.3 +/- 11% vs. delta 9.6 +/- 12%; p = NS) and decreased LVEDD (delta 3.7 +/- 5.5 mm/m2 vs. delta 3.7 +/- 7.4 mm/m2; p = NS). We found a higher percentage of clinical responders in patients with very dilated cardiomyopathy (96% vs. 72%, p < 0.05). CONCLUSION: In this study, a significant number of responders showed reverse remodeling after CRT. Although a higher percentage of patients with very dilated cardiomyopathy showed improvement in functional class, the extent of reverse remodeling was similar in both groups.

Modulação Eletrofisiológica das Aurículas e Veias Pulmonares: Interação da Estimulação Simpática e Parassimpática na Inducibilidade de Fibrilhação Aguda Auricular num Modelo Experimental In Vivo

A influência do sistema nervoso autónomo (SNA) na génese da fibrilhac¸ão auricular (FA) envolve múltiplos mecanismos complexos com impacto nas propriedades eletrofisiológicas cardíacas. A importância dos efeitos da estimulac¸ão autonómica no substrato elétrico auricular e das veias pulmonares (VP) e na vulnerabilidade para FA requer melhor compreensão. Objetivo: Avaliar os efeitos da estimulac¸ão vagal (estim vag) e simpática (estim simp) aguda na condução e refratariedade das aurículas e VP e na indutibilidade de FA no coração de coelho in vivo com inervação autonómica preservada. Métodos: Estudámos 17 coelhos New Zealand de ambos os sexos. Para abordagem de «toráxaberto» procedeu-se a anestesia, entubação e ventilação após bloqueio neuro-muscular. O ECG foi obtido a partir de 3 derivações dos membros. Os eletrogramas foram registados com 4 elétrodos monopolares colocados na superfície epicárdica, distribuídos ao longo das aurículas e com um elétrodo circular adaptado à porção proximal das VP. Estimulou-se o nervo vago cervical direito e o tronco simpático torácico com elétrodos bipolares de platina. Estudámos os períodos refratários efetivos (PRE) e a condução elétrica auricular, entre a aurícula direita lateral-alta (AD) e a aurícula esquerda lateral-alta (AE), e entre AD e VP, em condições basais e durante estim vag, estim simp e estimulação autonómica combinada (dual estim). Para indução de FA, procedeu-se a pacing rápido (50 Hz, 10 s, isolado ou com estim vag, estim simp ou dual estim) com elétrodo bipolar no apêndice auricular direito (AAD), apêndice auricular esquerdo (AAE) e VP. Resultados: Em condições basais: os PRE eram maiores no AAE e registou-se um atraso na ativação da AD para as VP, comparando com a condução interauricular. Durante estim vag ou dual estim: os PRE encurtaram significativamente em todos os locais, o intervalo de condução interauricular variou de 20 ± 4 ms para 30 ± 10 ms (p < 0,05) e 31 ± 11 ms (p < 0,05),respetivamente. Com estim simp obteve-se uma redução significativa dos PRE no AAE e do tempo de condução interauricular para 16 ± 11 ms (p < 0,05). Induziu-se FA em 35 a 53% dos animais com 50 Hz, 65 a 76% com estim vagal ou estim simp, e 75 a 100% com dual estim (p < 0,05). A duração da FA aumentou significativamente durante estim vagal e/ou estim simp. Em 2/3 dos animais com indução de FA com duração >10 s a arritmia terminou imediatamente após interrupção da estim vagal. Conclusões: No coração de coelho inervado in vivo, a estimulação autonómica aguda encurta a refratariedade auricular e das VP, e modifica a velocidade de condução auricular, potenciando a indução e duração de FA. Os resultados sugerem que as variações agudas e a interação da atividade autonómica podem desempenhar um papel importante na fisiopatologia da FA.

Impedimentos à Prescrição de Anticoagulação na Fibrilhação Auricular e Atitude Face aos Novos Anticoagulantes Orais

Introdução e Objetivos: Avaliar a taxa de prescrição de anticoagulantes orais na fibrilhação auricular, os fatores associados à não prescrição, os motivos referidos pelos clínicos para não prescrição de anticoagulantes incluindo os de nova geração e realizar estudo evolutivo a médio prazo. Material e Métodos: Estudo prospetivo sobre casos consecutivos de doentes com fibrilhação auricular com alta hospitalar. Registaram- se os scores CHA2DS2VASc e HASBLED, comorbilidades associadas e a medicação prévia e à data de alta. Na alta hospitalar, o médico assistente indicou em questionário o motivo de não prescrição de anticoagulantes orais e dos novos anticoagulantes orais. Exclusão: contra-indicação absoluta para anticoagulação, CHA2DS2VASc ≤ 1 e doença valvular. Os doentes foram reavaliados um ano após o recrutamento do primeiro doente. Resultados: Identificaram-se 103 candidatos a anticoagulação oral (79,6 ± 8,0 anos; CHA2DS2VASc 5,8 ± 1,4; HASBLED 2,6 ± 1,0; HASBLED ≥ 3 em 55,3%); os anticoagulantes foram prescritos em 34,0%. Fatores associados à não prescrição por ordem decrescente de relevância: uso prévio de antiagregantes, doente acamado e/ou demente, ausência de insuficiência cardíaca e número de fatores de risco hemorrágico. Razões invocadas para não prescrição por ordem decrescente de frequência: risco hemorrágico elevado, pequeno benefício, incapacidade de seguir o esquema terapêutico e dificuldade na monitorização da razão normalizada internacional(INR). Os novos anticoagulantes não foram prescritos e as razões invocadas foram, por ordem decrescente de frequência: informação insuficiente sobre estes fármacos, risco hemorrágico elevado, custo elevado e pequeno benefício. Aos 8,2 ± 2,5 meses de estudo evolutivo 33,3% dos doentes encontravam-se sob anticoagulação sem que os novos anticoagulantes tivessem sido prescritos. Conclusões: Nesta amostra, a taxa de prescrição de anticoagulação oral foi baixa e o fator mais associado à não prescrição foi o uso prévio de antiagregantes. O impedimento à prescrição mais referido foi o risco hemorrágico, seguido do pequeno benefício reconhecido. Os principais impedimentos referidos à prescrição dos novos anticoagulantes foram a informação insuficiente e o alto risco hemorrágico. A médio prazo, a proporção de doentes sob anticoagulação mantinha-se baixa e os novos anticoagulantes não tinham sido prescritos.

Iatrogenic Aortic Pseudoaneurysm: a Forgotten Complication

Pseudoaneurysms of the ascending aorta are a rare complication of cardiac surgery. However, the poor prognosis associated with this condition if untreated makes early diagnosis and treatment important. We present the case of a 66-year-old woman who had undergone mitral valvuloplasty 12 days previously, who was admitted with a diagnosis of new-onset atrial fibrillation. The transthoracic echocardiogram showed a clot in the right atrium and anticoagulation was initiated, followed by antibiotic therapy. After further investigation, the patient was diagnosed with a pseudoaneurysm of the ascending aorta and underwent surgical repair, followed by six weeks of antibiotic therapy. She was readmitted six months later for an abscess of the lower sternum and mediastinum. After a conservative approach with antibiotics and local drainage failed, recurrence of a large pseudoaneurysm compressing the superior vena cava was documented. A third operation was performed to debride the infected tissue and to place an aortic allograft. There were no postoperative complications.

National Registry on Cardiac Electrophysiology (2012)

Based on a survey sent to Portuguese centers that perform diagnostic and interventional electrophysiology and/or implantable cardioverter-defibrillator (ICD) implantations, the authors analyze the number and type of procedures performed during 2012 and compare these data with previous years. In 2012, a total of 2561 diagnostic electrophysiologic studies were performed, which were followed by ablation in 2017 cases, representing a steady situation compared with the previous year. There was a 12% increase in the number of ablation procedures for atrial fibrillation, making it for the first time the most frequent indication for ablation, overtaking atrioventricular nodal reentrant tachycardia. The total number of first ICD implantations was 1048 (around 100 per million population), of which 375 were cardiac resynchronization devices (BiV ICDs). This represents a slight decrease (3.3%) in the total number of new implants, with an increase of 10% in the number of BiV ICDs compared to the previous year. However, there was a considerable increase in the number of ICD generator replacements, resulting in an overall increase of 3.5% in implantations performed in 2012. Some comments are made regarding developments in this activity and its current status, and on some factors that may influence the dynamics of this area of interventional cardiology.

Duração dos Episódios de Fibrilhação Auricular e Implicações no Risco Tromboembólico

Introdução: A fibrilhação auricular é uma arritmia comum e com risco tromboembólico bem documentado, estando definidas nas recomendações internacionais indicações referentes ao uso de anticoagulantes orais. Existem, contudo, lacunas de informação nomeadamente no que se refere à duração dos episódios de fibrilhação auricular e sua relação com o risco de tromboembolismo. Esta questão tem particular interesse em doentes com dispositivos electrónicos cardíacos implantados com documentação contínua da duração de episódios de taquidisritmias auriculares, que são frequentemente curtos e assintomáticos. Material e Métodos: Foi feita uma análise crítica da evidência disponível sobre a relação da duração dos episódios de FA paroxística e a ocorrência de eventos embólicos, com base numa pesquisa na base de dados bibliográfica PubMed. Resultados: Foram selecionados oito artigos com abordagens diferentes no estudo deste tema; sete com recurso a monitorização cardíaca com dispositivos electrónicos cardíacos implantados (pacemakers, cardioversores-desfibilhadores implantáveis e ressincronizadores cardíacos) e um com base em registo de Holter. Metade destas publicações, correspondendo globalmente às maiores amostragens, aborda a questão do ponto de vista do somatório diário de episódios de fibrilhação auricular (carga diária) e não da duração de cada episódio. O risco tromboembólico aumenta gradualmente com a carga arrítmica, tendo sido demonstrado um aumento significativo do risco quando esta ultrapassa os cinco minutos num dia. Discussão: A formação de um trombo intracavitário, e consequente potencial embólico, é um processo dinâmico que resulta da interacção de várias condicionantes anatómicas e funcionais. O risco individual dependerá da interacção destes factores. A associação entre fenómenos embólicos e curtos períodos de fibrilhação auricular é inequívoca, apesar do mecanismo não ser óbvio, tendo em conta a discrepância frequentemente observada entre os períodos de fibrilhação auricular e os eventos clínicos. Conclusões: O risco de eventos tromboembólicos aumenta significativamente mesmo para períodos curtos de fibrilhação auricular (≥ cinco minutos de fibrilhação auricular em um dia), apesar da relação causa-efeito não estar definida. A decisão final sobre o recurso à anticoagulação oral deve basear-se na avaliação clínica individualizada.

Epigastric pain: incarceration or rotation?

Introduction: Acute intrathoracic gastric volvulus occurs when the stomach has a twist mesenteroaxial/organoaxial or chest cavity resulting in a dilatation or rupture of the diaphragmatic hiatus or diaphragmatic hernia. The purpose of this work is to show a interesting case of gastric volvulus in a patient with several comorbidities. Case Report: A 77-year-old female with past history of hiatal hernia and mental disease associated with diabetes and atrial fibrillation. Patient went to the emergency department due to vomiting associated with blood. Analytical parameters (WBC, HGB, PCR, metabolic panel and liver function), showed no significant alterations. Thoracic X-ray revealed an enlarged mediastinum due to herniation of the stomach. A computed tomography (CT) scan confirmed intrathoracic localization of the gastric antrum with twist. Patient’s symptoms were relieved by nasogastric intubation and analgesia. After six months, the patient is still asymptomatic. Conclusion: In general, the treatment of an acute gastric volvulus requires an emergent surgical repair. In patients who are not surgical candidates (with comorbidities or an inability to tolerate anesthesia), endoscopic reduction should be attempted. Chronic gastric volvulus may be treated non-emergently, and surgical treatment is increasingly being performed using a laparoscopic approach. In this case, it is a chronic form that was solved with the placement of the nasogastric tube. A nasogastric decompression is an option in the chronic form of hiatal hernia associated to gastric volvulus in patients with serious comorbidities.

Atrial infarction is a unique and often unrecognized clinical entity

A patient with heart failure and acute atrial fibrillation received the final diagnosis of atrial infarction associated with ventricular infarction based on clinical findings of ischemia in association with atrial fibrillation and heart failure (mechanisms probably involved: contractile dysfunction and loss of atrial contribution). Although a transesophageal echocardiography, which could refine the diagnosis of anatomic abnormalities, was not performed, all evidence led to the diagnosis of atrial involvement. Electrocardiographic findings were consistent with Liu's major criterion 3. Therapy with digitalis, quinidine and angiotensin-converting enzyme inhibitors was chosen, as the patient had acute pulmonary edema. The use of beta-blockers and verapamil was restricted. No other complications, such as thrombo-embolism or atrial rupture, were noted.

Immediate and long term evolution of valve replacement in children less than 12 years old

OBJECTIVE: The aim of this work was the follow-up and evaluation of valve replacement in children under 12 years of age. METHODS: Forty-four children less than 12 years old were underwent valve replacement at INCOR-HCFMUSP between January 1986 and December 1992. Forty (91%) were rheumatic, 39 (88.7%) were in functional classes II or IV, 19 (43.2%) were operated upon on an emergency basis, and 6 (13.6%) had atrial fibrillation. Biological prostheses (BP) were employed in 26 patients (59.1%), and mechanical prostheses (MP) in 18 (40.9%). Mitral valves were replaced in 30 (68.7%), aortic valves in 8 (18.2%), a tricuspid valve in 1 (2.3%), and double (aortic and mitral) valves in 5 (11.4) of the patients. RESULTS: Hospital mortality was of 4.5% (2 cases). The mean follow-up period was 5.8 years. Re-operations occurred in 63.3% of the patients with BP and in 12.5% of those with MP (p=0.002). Infectious endocarditis was present in 26.3% of the BP, but in none of the cases of MP (p=0.049). Thrombosis occurred in 2 (12.5%) and hemorrhage in one (6.5%) of the patients with a MP. Delayed mortality occurred in 5 (11.9%) of the patients over a mean period of 2.6 years; four had had BP and one had a MP (NS). Actuarial survival and re-operation-free curves after 10 years were respectively, 82.5±7.7 (SD)% and 20.6±15.9%. CONCLUSION: Patients with MP required fewer re-operation, had less infectious endocarditis and lower late mortality rates compared with patients with bioprostheses. The former, therefore, appear to be the best valve replacement for pediatric patients.

Right ventricular bifocal stimulation in the treatment of dilated cardiomyopathy with heart failure

OBJECTIVE: To describe a new more efficient method of endocardial cardiac stimulation, which produces a narrower QRS without using the coronary sinus or cardiac veins. METHODS: We studied 5 patients with severe dilated cardiomyopathy, chronic atrial fibrillation and AV block, who underwent definitive endocardial pacemaker implantation, with 2 leads, in the RV, one in the apex and the other in the interventricular septum (sub pulmonary), connected, respectively, to ventricular and atrial bicameral pacemaker outputs. Using Doppler echocardiography, we compared, in the same patient, conventional (VVI), high septal ("AAI") and bifocal ("DDT" with AV interval ~ 0) stimulation. RESULTS: The RV bifocal stimulation had the best results with an increase in ejection fraction and cardiac output and reduction in QRS duration, mitral regurgitation and in the left atrium area (p <= 0.01). The conventional method of stimulation showed the worst result. CONCLUSION: These results suggest that, when left ventricular stimulation is not possible, right ventricular bifocal stimulation should be used in patients with severe cardiomyopathy where a pacemaker is indicated.

Peripheral arterial embolism. Report of hospitalized cases

OBJECTIVE: We analyzed the frequency of peripheral embolisms, the underlying heart disease,triggering factors, the sites of the emboli, and evolution of the patients. METHODS: We analyzed 29 cases of peripheral arterial embolism out of a total of 20,211 hospitalizations in a cardiology center in the city of São Paulo. The age was 51.89±18.66 years, and 15 were males. RESULTS: Embolism in the right lower limb occurred in 18 patients (62.0%),in the left lower 11(37.9%) and right upper 3 (10.3%) limbs, and in the left arm (1). Four patients had embolism in two limbs. The heart disease, mitral valvar heart disease (9 patients - 31.0%); infective endocarditis (7- 24.1%); dilated cardiomyopathy (6 - 20.6%); ischemic coronary heart disease (6 patients - 20.6%); and one patient with cor pulmonale. Atrial fibrillation was observed in 20 patients (68.9%), chronic in 12 patients (41.3% ) and acute in 8 (27.5%). All patients with mitral valvar heart disease had atrial fibrillation, chronic in 8 patients (88.8%); patients with cardiomyopathy and coronary heart disease, 4 in each group had atrial fibrillation, acute in 60% of the patients.Patients with infective endocarditis, 3 had staphylococcus and 2 Gram-negative bacteria. In the follow-up, 2 patients (6.8%) required limbs amputation, and 5 (17.2%) died due to embolism. CONCLUSION: Most of the time, embolism does not cause permanent complications. Our data highlight the importance of anticoagulation for patients acute atrial fibrillation in myocardial dysfunction and for patients with chronic atrial fibrillation in cases of mitral valvar heart disease to prevent peripheral embolism.

Predictive value of clinical and electrophysiological variables in patients with chronic chagasic cardiomyopathy and nonsustained ventricular tachycardia

OBJECTIVE: Risk stratification of patients with nonsustained ventricular tachycardia (NSVT) and chronic chagasic cardiomyopathy (CCC). METHODS: Seventy eight patients with CCC and NSVT were consecutively and prospectively studied. All patients underwent to 24-hour Holter monitoring, radioisotopic ventriculography, left ventricular angiography, and electrophysiologic study. With programmed ventricular stimulation. RESULTS: Sustained monomorphic ventricular tachycardia (SMVT) was induced in 25 patients (32%), NSVT in 20 (25.6%) and ventricular fibrillation in 4 (5.1%). In 29 patients (37.2%) no arrhythmia was inducible. During a 55.7-month-follow-up, 22 (28.2%) patients died, 16 due to sudden death, 2 due to nonsudden cardiac death and 4 due to noncardiac death. Logistic regression analysis showed that induction was the independent and main variable that predicted the occurrence of subsequent events and cardiac death (probability of 2.56 and 2.17, respectively). The Mantel-Haenszel chi-square test showed that survival probability was significantly lower in the inducible group than in the noninductible group. The percentage of patients free of events was significantly higher in the noninducible group. CONCLUSION: Induction of SMVT during programmed ventricular stimulation was a predictor of arrhythmia occurrence cardiac death and general mortality in patients with CCC and NSVT.

Influence of the echocardiographic score and not of the previous surgical mitral commissurotomy on the outcome of percutaneous mitral balloon valvuloplasty

OBJECTIVE: To evaluate prior mitral surgical commissurotomy and echocardiographic score influence on the outcomes and complications of percutaneous mitral balloon valvuloplasty. METHODS: We performed 459 complete mitral valvuloplasty procedures. Four hundred thirteen were primary valvuloplasty and 46 were in patients who had undergone prior surgical commissurotomy. The prior commissurotomy group was older, had higher echo scores, and a tendency toward a higher percentage of atrial fibrillation. RESULTS: When the groups were compared with each other, no differences were found in pre- and postprocedure mean pulmonary artery pressure, mean mitral gradient, mitral valve area, and mitral regurgitation . Because we found no significant differences, we subdivided the entire group based on echo scores, those with echo scores <=8 and those with echo scores >8 the mitral valve area being higher in the <=8 echo score group 2.06±0.42 versus 1.90±0.40cm² (p=0.0090) in the >8 echo score group. CONCLUSION: Dividing the groups based on echo score revealed that the higher echo score group had smaller mitral valve areas postvalvuloplasty.

Prognostic factors of the results of cardiopulmonary resuscitation in a cardiology hospital

OBJECTIVE: To analyze the early and late results of cardiopulmonary resuscitation in a cardiology hospital and to try to detect prognostic determinants of both short- and long-term survival. METHODS: A series of 557 patients who suffered cardiorespiratory arrest (CRA) at the Dante Pazzanese Cardiology Institute over a period of 5 years was analyzed to examine factors predicting successful resuscitation and long-term survival. RESULTS: Ressuscitation maneuvers were tried in 536 patients; 281 patients (52.4%) died immediately, and 164 patients (30.6%) survived for than 24 hours. The 87 patients who survived for more than 1 month after CRA were compared with nonsurvivors. Coronary disease, cardiomyopathy, and valvular disease had a better prognosis. Primary arrhythmia occurred in 73.5% of the >1-month survivor group and heart failure occurred in 12.6% of this group. In those patients in whom the initial mechanism of CRA was ventricular fibrillation, 33.3% survived for more than 1 month, but of those with ventricular asystole only 4.3% survived. None of the 10 patients with electromechanical dissociation survived. There was worse prognosis in patients included in the extreme age groups (zero to 10 years and 70 years or more). The best results occurred when the cardiac arrest took place in the catheterization laboratories. The worst results occurred in the intensive care unit and the hemodialysis room. CONCLUSION: The results in our series may serve as a helpful guide to physicians with the difficult task of deciding when not to resuscitate or when to stop resuscitation efforts.

Clinical Meaning of Ascites in Patients with Endomyocardial Fibrosis

OBJECTIVE: To evaluate the clinical meaning of ascites and the main features of patients with ascites and endomyocardial fibrosis. METHODS: We studied 166 patients with endomyocardial fibrosis (mean age 37 years, 114 women) treated over the last 20 years. Ventriculography findings, surgery or necropsy confirmed the diagnosis in all patients. Most patients belonged to New York Heart Association Functional Class III/IV (134, 83.7%). Eighty-one (50.6%) had biventricular, 28 (17.5%) had right ventricular, and 51 (31.8%) had left ventricular involvement. During follow-up, 56 patients died. RESULTS: Ascites was present in 67 (41.8%) patients, and right ventricular involvement was present in 59 (88%). In the comparison between patients with or without ascites, those with ascites had higher mortality (49.2% and 24.7%, respectively). Patients with ascites had a higher incidence of edema (95% vs. 43%), hepatomegaly (5.8cm vs. 4.1cm), mean right atrium pressure (19.3 vs. 12mmHg), and final right ventricle diastolic pressure (18.7 vs. 12.9mmHg). Also, patients with ascites had a longer history of illness (5.1 and 3.9 years, respectively) and had atrial fibrillation more frequently (44.7% vs. 30.1%). CONCLUSION: Ascites was observed in less than 50% of cases of endomyocardial fibrosis and was associated with greater involvement of the right ventricle and with a longer duration of the disease, thus being a characteristic of a worse prognosis.