Ventriculectomia parcial esquerda: ponte para transplante em pacientes com insuficiência cardíaca refratária e hipertensão pulmonar

Abstract

A insuficiência cardíaca congestiva refratária a tratamento clínico tem no transplante cardíaco ortotópico a sua melhor opção cirúrgica. Escassez de doadores, morbidade significativa associada com a terapêutica anti-rejeição, aterosclerose coronária e custos consideráveis associados com o transplante são fatores responsáveis pela sua limitada aplicação. Para os que se encontram na lista para transplante, o período de espera de 6 meses a 1 ano pode levar à deterioração hemodinâmica e expressivo número de mortes. A sobrevida, na lista de espera, pode ser de 46% em 1 ano (1). Afora isso, um significativo número de pacientes tem contra-indicação para transplante, por apresentar hipertensão e resitência pulmonar elevadas. A ventriculectomia parcial esquerda (VPE) (2, 3), restaurando o raio do ventrículo esquerdo e melhorando, assim, a relação massa-volume e o desempenho sistólico, pode propiciar diminuição da pressão e da resistência arterial pulmonar, em alguns pacientes.<br>Medically refractory heart failure is traditionally managed with cardiac transplantation although some limited success has also been obtained in selected patients with alternative surgical options. Scarce donors, significant morbidity secondary to the antirejection therapy, post-transplantation coronary disease and the high costs of transplantation programs, all together are limiting factors. For those on the waiting list of transplantation the one year mortality may be as high as 46%. Furthermore, a significant number of patients have contraindication to transplantation due to severe pulmonary arterial hypertension and elevated pulmonary vascular resistance. Partial Left Ventriculectomy (PLV) attempts to relieve symptoms of congestive heart failure by reducing left ventricular dimensions and mass and restoring the normal mass-to-volume ratio of the left ventricle. As a consequence, cardiac index and forward ejection fraction increase thus unloading the pulmonary vascular bed. The ultimate result is a decrease in both pulmonary arterial pressure and resistance, in some patients

Partial left ventriculectomy: a retrospective study

“…This was expressed according to the perspective of the patient and assessed by the increase in the "quality of life score"-physical performance, performance at work, psychological condition, sleep pattern, eating habits, perception of symptoms, quality of social interaction, feelings and expectations related to treatment [53]. These findings seem well consistent with the notion that in heart failure, morbidity progresses in parallel with the dilation of the LV chamber [54] and that the improvement in the quality of life might also be an indication for a change in the functional class [25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41]. However, after PLV, neither "requalification", that is impossible to numerical express, which predominates in the evaluation of "quality of life", nor increase in ejection indices that can, numerically, characterize improvement in functional performance, seem to be reliable predictors of a post-operative evolution with sustained functional improvements free of fatal arrhythmias.…”

“…Among other publications, the same quantitative parameters for ventricular reduction were indistinctly applied to all ventricular dilations [25] and the same "surgical reconstruction" model has been used for left ventricular reconstruction with different patterns of chamber dilation [6]. The predominance of diffuse or segmental anomalies in the distribution of the mass or the tolerance of the LV were never taken into account [25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41].…”

“…Ischemic disease and Chagas' Disease, critical determinants of anomalies of contractility and of the load distribution on the LV, characterize peculiar geometric patterns and represent, with all probability, the least apt population to benefit from PLV [25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41].…”

“…In spite of the scarcity of specific information [25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41], it seems to be consensual that the worst clinical results can be expected in patients with dilations characterized by segmental anomalies of the LV wall.…”

“…No clinical evidence that enabled a clear choice has been found, whether for systematic valve replacement, or conservation of the mitral apparatus. The occurrence of some degree of mitral regurgitation in the post-operative period seems to have been a common event [25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41], not correlated with the degree of mitral insufficiency, nor with the pre-operative myocardial competence [52]. However, the post-operative progression of mitral insufficiency seems to have been an important marker of death [25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41].…”