Heart rate variability in patients with orthotopic heart transplantation: long-term follow-up.

To evaluate heart rate variability (expressed as the standard deviation of RR intervals) within 5 years of follow-up, we studied 20 patients (14 males, 6 females, mean age 44 +/- 12 years) who underwent orthotopic heart transplantation. Six measurements were taken: one in the first 3 weeks after transplantation, and the others once annually, for 5 years. Twenty healthy subjects (mean age 44 +/- 7 years) constituted the control group. Heart rate variability increased significantly in the first 3 years of follow-up (7.2 +/- 1 vs. 11.1 +/- 4, p < 0.001; 11.1 +/- 4 vs. 15.2 +/- 4, p < 0.01; 15.2 +/- 4 vs. 18.9 +/- 5, p < 0.05); in the following years this trend slackened and values did not reach a statistically significant difference (18.9 +/- 5 vs. 21.4 +/- 5; 21.4 +/- 5 vs. 22.5 +/- 5). The mean standard deviation was invariably greater in the control group (63.6 +/- 12). These findings show that sinus rhythm variability in the denervated heart progressively increased over 5 years of follow-up. The absence of presynaptic uptake, which is responsible for adrenergic hypersensitivity to circulating catecholamines and intrinsic cardiac reflexes, does not appear to cause this phenomenon, since these mechanisms are not able to evolve in time after cardiac transplantation. Therefore, an enhanced beta-adrenergic receptors density or affinity to circulating catecholamines or a limited sympathetic reinnervation may be the more probable underlying mechanism.

[Short- and mid-term results of percutaneous aortic valvuloplasty for calcific aortic stenosis in elderly patients]. / Risultati a breve e medio termine della valvuloplastica aortica percutanea nel trattamento della stenosi aortica calcifica dell'anziano.

In order to evaluate the short and mid-term results of percutaneous aortic balloon valvuloplasty, 40 consecutive elderly patients with symptomatic severe calcific aortic stenosis, underwent the procedure consecutively, with follow-up by clinical evaluation and Doppler echocardiography. Over a mean follow-up period of 11.2 months there were 5 deaths, and 12 patients underwent subsequent aortic valve replacement. Doppler echocardiography revealed an increase in aortic valve area from 0.62 +/- 0.20 cm2 to 0.91 +/- 0.23 cm2 after the procedure, but there was a significant trend toward restenosis by 12 months follow-up in 23 of 32 patients (72%). Restenosis was accompanied by symptomatic deterioration in 18 of 23 patients (78%). Although balloon valvuloplasty may often improve haemodynamics and relieve symptoms, these benefits seem to be short-lived in most cases. Restenosis has a high rate of occurrence. Aortic balloon valvuloplasty should be reserved for truly inoperable cases and for haemodynamically-unstable patients, who may later undergo surgery.