Paradoxical Heart Failure Precipitated by Profound Dehydration: Intraventricular Dynamic Obstruction and Significant Mitral Regurgitation in a Volume-Depleted Heart

Occurrence of dynamic left ventricular outflow tract (LVOT) obstruction is not infrequent in critically ill patients, and it is associated with potential danger. Here, we report a case of transient heart failure with hemodynamic deterioration paradoxically induced by extreme dehydration. This article describes clinical features of the patient and echocardiographic findings of dynamic LVOT obstruction and significant mitral regurgitation caused by systolic anterior motion of the mitral valve in a volume-depleted heart.

Implante de stent na via de saída de ventrículo direito: alternativa à paliação cirúrgica convencional? / Stenting the right ventricle outflow tract: is it an alternative to palliative surgery?

O uso de stents intravasculares em crianças com cardiopatia congênita é procedimento bem estabelecido, porém a indicação de paliação por meio de procedimentos percutâneos ao invés da cirurgia convencional permanece incerta. Neste relato são apresentados três casos de obstrução crítica de via de saída do ventrículo direito (VSVD), submetidos a ampliação da VSVD com implante de stent. O implante foi realizado com sucesso nos três casos, permitindo restabelecer o fluxo pulmonar para a árvore pulmonar e melhorar a saturação de oxigênio.

The use of intravascular stents in children with congenital heart disease is well established, however the use of palliative percutaneous therapy instead of a conventional surgery remains uncertain. We present three cases of critical right ventricular outflow tract (RVOT) obstruction treated with stenting to expand the RVOT. Stenting was successful in all three cases, reestablishing pulmonary flow into the pulmonary arteries and improving oxygen saturation.

Ablação com radiofreqüência de extra-sístoles da via de saída do ventrículo direito / Radiofrequency catheter ablation of premature ventricular contractions originating in the right ventricular outflow tract

OBJETIVOS: Avaliar se a ablação com radiofreqüência é um procedimento eficiente para o tratamento das extra-sístoles da via de saída do ventrículo direito (EVSVD), e se resulta em melhora dos sintomas. MÉTODOS: Estudo prospectivo, com 30 pacientes consecutivos (idade média de 40±13 anos, 25 do sexo feminino), sem cardiopatia estrutural aparente, com EVSVD, muito freqüentes (densidade média de 1.263±593/h), sintomáticos por mais de 1 ano (média =74 meses) e refratários aos fármacos antiarrítmicos (3±1,7, incluindo os beta-bloqueadores), que foram submetidos à ablação com radiofreqüência. RESULTADOS: Após o primeiro procedimento, houve 23 sucessos iniciais (76,6 por cento) e 7 iniciais insucessos (23,4 por cento). Quatro pacientes tiveram recorrências, sendo que dois desses não se submeteram ao segundo procedimento. O segundo procedimento foi realizado em 9 pacientes (7 insucessos iniciais e 2 recorrências), e o sucesso ocorreu em 5 pacientes adicionais, sendo 1 caso por acesso epicárdico. A taxa de sucesso final foi de 80 por cento (24/30), e nenhuma complicação maior ocorreu. Após um seguimento médio de 14±6 meses, no grupo de sucesso final houve uma redução de mais de 90 por cento na densidade das extra-sístoles(24/24; p<0,0001) e resultante ausência de sintomas na maioria dos pacientes (23/24; p<0,001). CONCLUSÃO: A ablação com radiofreqüência é um tratamento seguro e eficaz para os pacientes com extra-sístoles persistentes e sintomáticas com morfologia do trato de saída do ventrículo direito.

OBJECTIVES: To evaluate if radiofrequency catheter ablation is an effective procedure for the treatment of right ventricular outflow tract premature ventricular contractions (RVOT-PVC) and ascertain if it results in an improvement of symptoms. METHODS: A prospective study with 30 consecutive patients (mean age 40 ± 13 years, 25 females), with no apparent structural cardiopathy, with very frequent (mean density of 1,263 ± 593/h) RVOT-PVC, symptomatic for more than one year (mean = 74 months) and resistant to antiarrhythmic drugs (3 ± 1.7, including beta-blockers), who underwent radiofrequency catheter ablation. RESULTS: After the first procedure, there were 23 initial successful cases (76.6 percent) and 7 initial failures (23.4 percent). Four patients experienced relapses, two of whom did not undergo the second procedure. The second procedure was carried out in 9 patients (7 initial failures and 2 relapses), and there was success in 5 additional patients, one of them by epicardial access. The final success rate was 80 percent (24/30), and there were no major complications. After a mean follow-up of 14 ± 6 months, in the successful group there was a reduction greater than 90 percent in density of premature ventricular contractions (PVC) (24/24; p<0.0001) and a resulting absence of symptoms in the majority of patients (23/24; p<0.001). CONCLUSION: Radiofrequency catheter ablation is a safe and effective treatment for patients with persistent and symptomatic PVC with RVOT morphology.

Estratégia cirúrgica na transposicão das grandes artérias com septo interventricular intacto após o período neonatal / Surgical strategy for transposition of the great arteries with intact ventricular septum after the neonatal period

OBJETIVO: Analisar o resultado cirúrgico em portadores de transposicão das grandes artérias com septo interventricular intacto, operados após o período neonatal. MÉTODOS: Entre janeiro de 1998 e marco de 2004 foram atendidas 121 criancas com transposicão das grandes artérias com septo interventricular intacto, sendo 29 (24 por cento) após o período neonatal. A selecão para tratamento cirúrgico foi baseada na avaliacão ecocardiográfica pelo cálculo da massa do ventrículo esquerdo e da configuracão do septo interventricular. Das 29 criancas, 12 foram selecionadas para correcão anatômica primária, 12 para correcão em dois estágios, após preparo cirúrgico do ventrículo esquerdo e 5 submetidas a correcão atrial. RESULTADOS: No grupo submetido à correcão anatômica primária houve 1 (8,3 por cento) óbito hospitalar por sepsis. No grupo de correcão em dois estágios, 5 pacientes foram submetidos ao preparo lento, com correcão 3-6 meses após o 1º estágio, ocorrendo 4 óbitos após o 1º estágio. Este fato determinou mudanca no nosso protocolo, adotando-se a técnica de preparo rápido nos outros 7 pacientes, tendo todos atingido o 2º estágio. Das 8 criancas submetidas ao 2º estágio houve 1 óbito hospitalar e outro óbito tardio. A evolucão clínica tardia das criancas de ambos os grupos é excelente. CONCLUSAO: A selecão ecocardiográfica adequada da transposicão de grandes artérias com septo interventricular intacto quando abordada após o período neonatal, permitiu uma orientacão segura da escolha da melhor abordagem cirúrgica nestes pacientes.

Radiofrequency catheter ablation of ventricular tachycardia from right ventricular outflow tract.

From January 1996 to May 2002, 61 patients with ventricular tachycardia from right ventricular outflow tract were referred to Siriraj hospital. All patients underwent clinical examination, Doppler echocardiography and electrophysiologic study. Mapping of ventricular tachycardia was performed by activation mapping and pacemapping. There were 44 females and 17 males with an average age of 41.7 +/- 9.9 years. Presenting symptoms were palpitation (95.1%), presyncope (39.3%), and syncope (26.2%). Six patients were found to have underlying cardiac disease. Radiofrequency catheter ablation was successful in 56 patients (91.8%). There were no major complications. Seven patients (12.5%) had recurrent ventricular tachycardia. Five of them were successfully reablated. The authors concluded that radiofrequency ablation is an effective treatment in patients with ventricular tachycardia from right ventricular outflow tract.

Left main coronary artery compression by dilated main pulmonary artery in endocardial cushion defect.

A 56-year-old man was evaluated for exertional dyspnoea. Chest X-ray showed mild cardiomegaly and a dilated main pulmonary artery. On echocardiogram he was found to have ostium primum atrial septal defect with moderate tricuspid insufficiency. Cardiac catheterization revealed an oximetry step-up of 14% at low right atrium with angiogram demonstrating a cleft in the mitral valve, an elongated left ventricular outflow tract and ventricular septal defect closed by a septal aneurysm. Coronary angiogram revealed ostial compression of the left main coronary artery with the rest of the coronary artery anatomy being normal.

Giant pulmonary artery aneurysm with right ventricular outflow tract obstruction.

Aneurysm of the main pulmonary artery is rare. Its natural history is not well understood and there are no clear guidelines regarding its optimal treatment. We present a case of a huge saccular aneurysm of the main pulmonary artery which was associated with infundibular and valvular pulmonary stenosis. It was repaired using a pericardial patch with concomitant pulmonary valvotomy and infundibular resection. Postoperative recovery was uneventful and the patient is doing well. Follow-up echocardiogram revealed good repair.

Aneurisma apical e hipertrofia ventricular esquerda / Apical aneurysm and left ventricular hypertrophy

A 59-year-old woman presented with an embolic transient ischemic attack and a history of controlled hypertension for 16 years. Both echocardiogram and MRI showed severe biventricular hypertrophy and an apical aneurysm with a thrombus. The occurrence of an apical aneurysm in the presence of cardiac hypertrophy is a rare finding and has been described in patients with hypertrophic cardiomyopathy. However, it has not been reported in patients with systemic arterial hypertension. In this patient the lack of a relationship between the severity of the hypertrophy and the levels of blood pressure, together with the presence of histologic disorganization of myocardial cardiac muscle cells by endomyocardial biopsy suggested the diagnosis of hypertrophic cardiomyopathy.

Transcatheter ablation of ventricular tachycardia arising from right ventricular outflow tract.

Two patients with recurrent episodes of symptomatic, sustained monomorphic ventricular tachycardia (VT) resistant to medical therapy underwent catheter ablation for the relief of VT. One patient had arrhythmogenic right ventricular dysplasia while the other had no structural heart disease. The VT had left bundle branch block morphology with normal axis in both the patients. The cycle length during VT was 260 msec and 270 msec respectively. Site for ablation was guided by pacemapping and the target site was identified in the right ventricular outflow tract in both the patients. Two cathodal shocks of 200 J in the first patient and one shock of 200 J in the second patient resulted in abolition of the arrhythmia. At repeat electrophysiologic testing at 7 days in the first patient and at 8 months in the second, VT was not inducible despite three extrastimuli from two right ventricular sites. Over a follow up of 24 and 26 months respectively, there has been no recurrence without any antiarrhythmic therapy. There were no acute or long term complications. In conclusion, catheter ablation offers a cure in patients with right ventricular tachycardia resistant to antiarrhythmic drugs.