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Background: Percutaneous myocardial revascularization with laser (PMR) is a catheter-based technique that has generated much interest in the treatment of patients with severe coronary artery disease. Several mechanisms have been proposed to explain the reported clinical benefits of this technique. Cardiac autonomic denervation is among these., Methods: We studied 32 consecutive patients with chronic severe angina not suitable for other revascularization approaches. Canadian Class Society (CCS) class clinical assessment, Naughton exercise stress test, and scintigraphic myocardial perfusion were evaluated before and 1 and 6 months after PMR. Ewing's autonomic tests, heart rate variability (HRV), and plasmatic catecholamines were assessed before revascularization in non-diabetic and diabetic patients and repeated 1 month after PMR in 13 non-diabetics. A psychological test was carried out before PMR to evaluate the attitude towards this new procedure., Results: All the markers of autonomic cardiac control were unmodified after the procedure. Moreover, scintigraphic perfusion measured in the lasered areas was similar before and after the procedure. On the other hand, the clinical conditions significantly improved (CCS class from 3+/-0.8 to 1.9+/-0.9 at 1 month, P<0.01) and the exercise-related ischemic threshold was significantly better (from 311+/-28 to 453+/-51 s, P<0.05). The patients with a psychologically 'positive' expectation for this new procedure had results comparable to those with a 'negative' expectation., Conclusions: PMR improves symptoms in patients with end-stage coronary artery disease in the absence of any detectable clinical sign of heart denervation.

Spectral analysis of skin blood flow has demonstrated low-frequency (LF, 0.03-0.15 Hz) and high-frequency (HF, 0.15-0.40 Hz) oscillations, similar to oscillations in R-R interval, systolic pressure, and muscle sympathetic nerve activity (MSNA). It is not known whether the oscillatory profile of skin blood flow is secondary to oscillations in arterial pressure or to oscillations in skin sympathetic nerve activity (SSNA). MSNA and SSNA differ markedly with regard to control mechanisms and morphology. MSNA contains vasoconstrictor fibers directed to muscle vasculature, closely regulated by baroreceptors. SSNA contains both vasomotor and sudomotor fibers, differentially responding to arousals and thermal stimuli. Nevertheless, MSNA and SSNA share certain common characteristics. We tested the hypothesis that LF and HF oscillatory components are evident in SSNA, similar to the oscillatory components present in MSNA. We studied 18 healthy normal subjects and obtained sequential measurements of MSNA and SSNA from the peroneal nerve during supine rest. Measurements were also obtained of the electrocardiogram, beat-by-beat blood pressure (Finapres), and respiration. Spectral analysis showed LF and HF oscillations in MSNA, coherent with similar oscillations in both R-R interval and systolic pressure. The HF oscillation of MSNA was coherent with respiration. Similarly, LF and HF spectral components were evident in SSNA variability, coherent with corresponding variability components of R-R interval and systolic pressure. HF oscillations of SSNA were coherent with respiration. Thus our data suggest that these oscillations may be fundamental characteristics shared by MSNA and SSNA, possibly reflecting common central mechanisms regulating sympathetic outflows subserving different regions and functions.