Innovative approaches to percutaneous bifurcation interventions using drug-eluting balloons.

Coronary bifurcations are frequently found complex coronary lesions that continue to be associated to worse outcomes than simpler ones, despite dedicated techniques and use of drug-eluting stents (DES). Moreover, besides concerns regarding DES thrombosis and late restenosis in complex lesions, several issues might limit DES use in real world conditions. If a widespread use of DES might therefore appeared unjustified, local treatment by an anti-proliferative drug remains attractive. This is the reason why drug-eluting balloons (DEB) have been developed, with several potential advantages over DES including homogeneous drug transfer to the vessel wall with local drug delivery over a very short period of time and absence of both a polymer matrix and a metal platform. When approaching bifurcation lesions, actual evidences do not support increased benefit of a two-stent technique over stenting the main vessel only. However, provisional stenting is often associated with suboptimal results in the side branch, thus leaving room for some improvement that could be very well managed by drug-eluting balloon technology. To date, two different approaches to percutaneous bifurcation intervention with DEB have been developed, namely sequential DEB treatment of the bifurcation branches followed by provisional bare metal stent implantation and simple main vessel stenting followed by kissing DEB. The kissing DEB approach has also shown promising results in the treatment of bifurcation restenosis that represent particularly challenging lesions to treat. Available data suggest that DEB offers a new opportunity to implement innovative, simpler and possibly safer and more effective percutaneous bifurcation interventions.

Endothelial dysfunction as assessed by flow-mediated dilation in patients with cardiac syndrome X: role of inflammation.

BACKGROUND: Endothelial dysfunction, reduced coronary flow reserve and increased markers of inflammation are detectable in cardiac syndrome X (CSX). In this study we investigated the relation between inflammation and systemic endothelial function in CSX patients. METHODS: We studied 42 CSX patients (55 +/- 6 years, 14 men) and 20 healthy subjects (52 +/- 7 years, 9 men). Systemic endothelial function was assessed by flow-mediated dilation (FMD) of the brachial artery after 5-minute of forearm cuff inflation. Serum C-reactive protein (CRP) was measured by a high-sensitivity method. RESULTS: FMD was significantly lower in CSX patients compared to controls (4.8 +/- 4.4 vs. 13.7 +/- 4%, p < 0.001), whereas CRP levels were higher in CSX patients than in controls (2.7 +/- 2.4 vs. 0.7 +/- 0.4 mg/L, p = 0.001). In CSX patients FMD showed a significant inverse correlation with CRP levels, even after adjustment for potentially confounding variables (r = -0.34, p = 0.006). CONCLUSION: An impaired FMD is detectable in CSX patients, suggesting a generalized abnormality in vascular function. Subclinical inflammation se is to play a significant role in the impairment of endothelium-dependent vasodilator function of these patients.

Effect of primary coronary intervention on heart rate variability and left ventricular function in patients with acute myocardial infarction.

AIM: Several studies showed that primary percutaneous coronary interventions (PCI) have a favourable impact on left ventricular remodeling and heart rate variability (HRV) both at short- and long-term follow-up in patients suffering an acute myocardial infarction (AMI). However, no previous study investigated the relationship between left ventricular remodeling and changes in HRV during follow-up in AMI patients treated by primary PCI. METHODS: We studied 28 patients with AMI (57+/-8 years, 27 men), treated by PCI within 12 hours of symptom onset. Patients underwent a 24-hour ECG Holter recording and left ventricular ejection fraction (LVEF) echocardiographic assessment before discharge, and at 1-month and 6-month follow-up. HRV was measured in the time- and frequency-domain. RESULTS: A significant improvement of both time- and frequency-domain HRV variables was observed at 1-month and at 6-month follow-up with the most significant changes being found for standard deviation of normal-normal beat intervals (SDNN) in the time-domain (95.5+/-26.1 ms vs 125.5+/-29.8 ms vs 142.8+/-28.8 ms, respectively; P<0.001) and for very low frequency (VLF) amplitude in the frequency-domain (36.7+/-9.8 ms vs 44.1+/-11.1 vs 48.9+/-12.2 ms, respectively; P<0.001). In contrast, compared to basal values, LVEF was substantially unchanged at 1-month and 6-month follow-up (48.8+/-8.5% vs 50.8+/-10% vs 49.6+/-9%, respectively; P=0.25). At 6-month follow-up 11 patients showed an improvement of >or= 5% of LVEF, whereas 17 patients did not show any improvement of LVEF. HRV variables significantly improved in a similar way in these two subgroups both at 1-month and at 6-month follow-up. CONCLUSION: Our data demonstrate that, in AMI patients treated by primary PCI, HRV improves over time, independent of changes in LVEF. The clinical implications of these findings deserve to be addressed in future studies.

Diagnostic and prognostic value of ST segment depression limited to the recovery phase of exercise stress test.

OBJECTIVES: To investigate the diagnostic and prognostic value of ST segment depression limited to the recovery phase of an exercise stress test, as compared with that of ST segment depression appearing during exercise. SETTING: Exercise stress test laboratory of a university hospital. PATIENTS AND DESIGN: Clinical and angiographic data were compared for 574 consecutive patients who developed ST segment depression during the active phase of an exercise test (group 1) and for 79 patients who developed ST segment depression only during the recovery phase of the exercise test (group 2). RESULTS: There were no differences between the two groups in major clinical features. Significant coronary artery stenoses were found in 488 group 1 patients (85%) and in 62 group 2 patients (78%, p = 0.14). Three vessel or left main disease was found in 166 (29%) group 1 and in 14 (18%) group 2 patients (p = 0.045). At a median follow up of 55.3 months of 321 group 1 and 54 group 2 patients, there were no significant differences in major cardiac events between the groups (univariate relative risk 0.81, 95% confidence interval 0.25 to 2.68, p = 0.72). CONCLUSION: The diagnostic and prognostic power of ST segment depression limited to the recovery phase of an exercise test is largely similar to that of ST segment depression induced during effort; thus, assessing ST segment depression during recovery can significantly improve the clinical information derived from exercise stress tests.