[Survival in patients with sick sinus syndrome and artificial pacemaker. Determining clinical factors]. / Supervivencia en pacientes con enfermedad del nodo sinusal portadores de marcapasos. Factores clínicos determinantes.

INTRODUCTION AND OBJECTIVE: The hypothesis that ventricular pacing is the most important factor in the survival of patients with Sick Sinus Syndrome remains controversial. The aim of this report was to determine independent clinical variables to predict survival in paced SSS patients. METHODS: Retrospective, nonrandomized study of 153 patients with a mean age of 69 +/- 11 years, who received an initial pacemaker for Sick Sinus Syndrome between 1980 and 1994: 65 physiologic pacing (32 dual chamber, 33 atrial) and 88 ventricular pacing mode. After a maximum follow up of 177 months (median 57 months) the end point was total mortality. RESULTS: Total mortality was 21%. Using univariate analysis, single chamber ventricular pacing, age > or = 70 years and NYHA > or = 2, was associated with a higher risk for total mortality (4 times increased risk for ventricular pacing compared to other pacing modalities). Independent predictors using multivariate analysis were: 1) NYHA > or = 2 (p < 0.05). 2) Coronary artery disease (p < 0.01). 3) Chronic obstructive pulmonary disease (p < 0.05) and 4) Gender (p < 0.05). CONCLUSIONS: Mortality in patients with the Sick Sinus Syndrome is strongly predicted by preimplant baseline clinical variables. Our data indicate that the role of ventricular pacing mode remains inconclusive. A large, randomized study is necessary to confirm these results.

[Persistence of the left superior vena cava associated with aortic insufficiency: diagnostic and therapeutic considerations]. / Persistencia de la vena cava superior izquierda asociada a insuficiencia aórtica: consideraciones diagnósticas y terapéuticas.

In the course of the routine evaluation of a 26-years-old male for acquired aortic valve disease the persistence of a left superior vena cava draining into the coronary sinus was detected. This is a frequent congenital malformation of the systemic venous system that has no hemodynamic consequences in itself, though it may be associated to other congenital or acquired cardiac malformations that may require surgery. The preoperatory detection of the anomaly prevents unexpected problems when connecting the cardiopulmonary bypass. We emphasize the importance of procedures that suggest the diagnosis and characterize the anatomo-functional nature of the condition--including transthoracic and transesophageal echocardiography using echocardiographic contrast, and cardiac catheterization with cardiac and vascular angiography.