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Objective: We analyzed the medium-term follow-up of cryoballoon ablation (CBA) for atrial fibrillation (AF) and the clinical risk factors predicting outcome., Methods: AF patients treated for the first time with CBA in a 4.5-year period were studied retrospectively. Pulmonary vein isolation (PVI) was achieved via a single cryoballoon with diameter of 28 mm. Left atrial diameter (LAD) was measured by transthoracic echocardiography. Failure of cryoablation treatment was defined as detection of an episode of AF, atrial flutter, or atrial tachycardia lasting more than 30 s during the 3-month follow-up., Results: A total of 212 patients were enrolled and in 87.7 % patients PVI was achieved by CBA. The complication rate was 2.83 %. The mean follow-up was 28 ± 15 months; in 166 patients follow-up was complete. The rate of successful treatment for primary CBA was 45.8 %. The percentage of patients who experienced atrial arrhythmia recurrence in the first 12 months was 84.44 %. Patients in whom treatment failed had a larger LAD (47 ± 6 mm vs. 43 ± 5 mm, p < 0.0001). The Kaplan-Meier curve showed that the patients with LAD < 45 mm had a higher success rate than patients with LAD ≥ 45 mm [57.9 % (44/76) vs. 35.6 % (32/90), log rank = 5.492, p = 0.019]. The LAD [odds ratio, OR = - 0.1053(0.303, 12.2040), p = 0.0005] was shown in logistic regression analysis to be independently predictive of CBA treatment failure., Conclusion: The CBA procedure for AF patients is safe and effective. Most atrial arrhythmia recurrences occurred during the first 12 months after CBA. The LAD can independently predict failure of CBA treatment.

Proprotein convertase subtilisin/kexin type 9 (PCSK 9) is a key regulator of cholesterol homeostasis acting via degradation of the low density lipoprotein (LDL) receptor. Loss of function PCSK 9 mutations result in very low LDL cholesterol serum levels and protection from cardiovascular disease whereas gain of function mutations increase serum LDL cholesterol. Based on in vitro and in vivo data antibodies targeting PCSK 9 have now emerged as a novel treatment option in patients with cardiovascular disease. This review briefly summarizes the biochemistry and function of PCSK9 and the results from recent phase II trials.

There is growing evidence that the noninvasive assessment of myocardial perfusion with cardiovascular magnetic resonance is a valid and accurate tool for the assessment of ischemic heart disease and its introduction into routine clinical evaluation of patients is rapidly expected. Magnetic resonance measurements allow the evaluation of reversible and irreversible myocardial ischemia, the assessment of acute myocardial infarction, as well as the recognition and detection of viable myocardium. Magnetic resonance perfusion measurements are mainly performed with T1-shortening contrast agents such as gadolinium-DTPA either by visual analysis or based on the analyses of signal intensity time curves. For the detection of myocardial ischemia the first pass kinetics of a gadolinium-DTPA bolus and for the detection of myocardial necrosis and the definition of viable myocardium steady state distribution kinetics are assessed. Quantitative analysis of myocardial perfusion can be performed but requires complex modeling due to the characteristics of gadolinium-DTPA. Thus, semi-quantitative parameters are preferred. There is accumulating evidence in the literature that magnetic resonance imaging can be used for the detection of coronary artery stenosis with high diagnostic accuracy both with semi-quantitative or visual analysis. Myocardial infarction can be reliably detected and the infarcted area determined. Non-reperfused infarcted myocardium can be differentiated from reperfused myocardium by different enhancement patterns that correlates with viability. Cardiac magnetic resonance is a promising technique that can combine different functional studies during one examination, such as the assessment of wall motion and perfusion at rest and stress. With further improvements in analysis software magnetic resonance perfusion measurement may rapidly become a routine tool for the assessment of patients with coronary artery disease.

Endothelial cells synthesize and metabolize vasoactive substances which are involved in the regulation of vascular tone. Among these factors, the endothelium-derived nitric oxide (NO) appears to be of major importance. Many studies observed an impairment of the generation, release, or the diffusion of endothelial NO across the vascular intima in laboratory animals with various experimental diseases such as hypercholesterolemia, atherosclerosis and hypertension. In human coronary arteries obtained from explanted hearts impaired endothelium-dependent relaxations were measured in atherosclerotic segments. The hypothesis of a decreased NO mediated vasodilation in patients with coronary artery disease was further underscored by in vivo studies in man using intracoronary infusions of the endothelium-dependent vasodilator acetylcholine and quantitative coronary angiographic measurements of the diameter changes. From these observations it was assumed that endothelial dysfunction, in particular a profound inability of the coronary endothelium to relax via NO dependent mechanisms may play an important role in the pathogenesis of abnormal coronary vasomotion. However, further investigations in man reveal that the ability of the coronary endothelium of patients with coronary artery disease or vasospastic angina to produce endothelial NO is less affected as judged from the effects of acetylcholine. In recent investigations a largely preserved endothelial function could be measured in these patients when the endothelium-dependent vasodilator substance P was used as a tool for the measurement of NO dependent relaxation. Thus, endothelial dysfunction does not appear to serve as a major cause of abnormal vasoconstriction in coronary artery disease or vasospastic angina in man.

Coronary artery fistulas have recently been reported to occur frequently in patients after heart transplantation due to repeated endomyocardial biopsies. To investigate if there is a relationship between development of coronary artery fistulas and the number of biopsies performed in transplanted patients, we studied the prevalence and localization of coronary artery fistulas in 168 patients after heart transplantation and in 100 control subjects. In addition to biplane ventriculography of the left ventricle, and in two-thirds of the patients the right ventricle as well, coronary angiography in multiple projections was performed at yearly intervals. The angiographic criterion for a coronary fistula was specified as visualization of a direct confluence from the arterial vascular lumen into a cardiac chamber, independent of size, which occurred prior to the venous phase, documented by opacification of the coronary sinus or great cardiac vein. The size of the fistula was assessed semi-quantitatively into one of three categories as small, barely detectable flow from a small arterial vessel with opacification of less than 10% of the involved chamber, large with direct flow from a large branch with opacification of more than one-third of the involved chamber (Figures 1a to 1c). Endomyocardial biopsies were performed weekly for the first three months after transplantation, thereafter, the interval was increased one week every three months. The prevalence of coronary fistulas in patients after heart transplantation was higher at 135/168 than in control subjects at 43/100. There were also more fistulas per patient (1.8 vs 0.67) in those transplanted than in control subjects (Figures 2a and 2b).(ABSTRACT TRUNCATED AT 250 WORDS)

To deal with the problem of restenosis after PTCA, several new methods and devices for treating atheromatous lesions have been developed. Among the promising techniques, is the opportunity to remove atheromatous material with the directional coronary atherectomy catheter designed by J.B. Simpson. The atherectomy catheter consists of a housing at the catheter tip with a concave cutting device which is rotated at a speed of 2000 r.p.m. The housing is positioned at the stenosis by means of a central guidewire; the material to be removed protrudes into the housing. With an inflatable balloon on the opposite side, the position of the housing is fixed in the coronary artery, the plaque is pressed further into the orifice and severed by the rotating blade. The material removed remains in the tip of the housing and can be used for morphologic examination as well as for functional studies with individual cell cultures. Experience published to date encompasses the results of 1032 treated stenoses. The majority of the treated lesions, 53%, were localized in the left anterior descending coronary artery; in 22% the lesion were located in the right coronary artery, in 17% in an aorto-coronary venous bypass graft. Due to the difficulty in positioning the relatively rigid atherectomy catheter, the method has only been employed in the circumflex artery in 6%. In a substantial number of patients, the stenoses had already been subjected to PTCA; in 57% of 963 patients treated with atherectomy, angioplasty had been performed previously, in 25% bypass grafting had been carried out. The primary success rate was 93%.(ABSTRACT TRUNCATED AT 250 WORDS)

While the technetium-99m-pyrophosphate scintigram enables diagnostic proof of acute myocardial infarction, its use in the evaluation of the extent of infarction has not been clearly established. This study, in 30 patients with acute myocardial infarction was, thus, undertaken to assess the relationship between the findings of the technetium-99m-pyrophosphate scintigram, with respect to infarct area and uptake pattern, the infarct size, as determined from the total CK an CK-MB curves, and the mortality. The scintigraphically determined infarct areas ranged between 1.7 and 29.3 cm2; the 20.2 plus or minus 6.0 cm2 average for anterior wall infarction (n=18, range 7.4 to 29.3 cm2) was significantly greater (p smaller than 0.005) than the 8.3 plus or minus 5.3 cm2 average for inferior infarction (n=12, range 1.7 to 15.8 cm2). Correlation coefficients between the scintigraphically and enzymatically determined infarct sizes for the entire patient population ranged from 0.71 to 0.80. Anterior infarctions correlated more closely (0.66 to 0.84) than inferior infarctions (0.46 to 0.66). The technetium-99m-pyrophosphate uptake pattern was focal in 20 patients and ring-shaped (doughnut) in ten. Infarcts with focal uptake patterns were significantly smaller than those displaying a doughnut pattern (12.2 plus or minus 6.4 vs. 24 plus or minus 4.0 cm2, p smaller than 0.005). The infarct weight calculated from the CK-MC curve with application of individually determined disappearance rate for those infarcts displaying a focal uptake pattern was 34 plus or minus 29 grams while that associated with a doughnut uptake pattern was significantly greater at 86 plus or minus 25 grams (p smaller than 0.005). During the 18 -month observation period there were six deaths; the average scintigraphic infarct area of 22.8 plus or minus 3.6 cm2 in those who died was significantly greater (p smaller than 0.005) than that of the 13.8 plus or minus 8.2 cm2 of the survivors. Of the non-survivors, five had a doughnut uptake pattern and one displayed focal uptake. In the 24 survivors, a focal uptake pattern was found in 19 and a doughnut pattern in five. Conversely, 19 of the 20 patients with a focal uptake pattern survived while only five of the ten patients with a doughnut pattern were alive after 18 months. Thus, comparison with the enzymatically determined infarct weight as well as the mortality indicate that the technetium-99m-pyrophosphate scintigram yields clinically relevant data with regard to infarct size. Since no patient with an infarct area of less than 17 cm2 died within the 18-month observation period, designation of scintigraphically determined infarct size as small (smaller than 17 cm2) and large (larger than 17 cm2) was enabled. The corresponding cut-off point between large and small infarctions as determined enzymatically has been designated at 65 grams. Accordingly, agreement was found in 70% (14 of 20 patients) with scintigraphically small infarcts and in 80% (8 of 10 patients) with scintigraphically large infarcts...

In 95 consecutive patients in whom 101 coronary artery stenoses were successfully dilated, angiography was performed before, immediately after and at an average of 6.6 months after the procedures with computer-derived stenosis measurements (based on three-dimensional vessel reconstruction). The results were referenced to an analysis of factors possibly exerting an influence on post-PTCA outcome. In 56 of the 101 dilated stenoses (minimal area prior to PTCA 0.83 +/- 0.57 mm2, after PTCA 4.09 +/- 1.7 mm2), the findings remained essentially unchanged throughout the six-month follow-up. 17 of the 56 dilated stenoses showed a further increase in minimal area as compared with the findings seen immediately after PTCA. A reduction of the minimal area of more than 1 mm2 from that achieved immediately after PTCA, associated with narrowing of the vascular lumen greater than 70% was found in 33 of the 101 stenoses (minimal area before PTCA 0.82 +/- 0.59 mm2, immediately after PTCA 3.92 +/- 1.55 mm2, six months post-PTCA 1.39 +/- 1.27 mm2). In twelve of the 101 stenoses, restenosis amounting to more than 1 mm2 was also observed but without critical compromise of the vascular lumen (minimal area before PTCA 0.81 +/- 0.39 mm2, immediately after PTCA 5.54 +/- 1.28, six months post-PTCA 3.22 +/- 1.43 mm2, corresponding to a mean luminal narrowing of 45 +/- 24%).(ABSTRACT TRUNCATED AT 250 WORDS)