Myocardin gene regulatory variants as surrogate markers of cardiac hypertrophy - study in a genetically homogeneous population

Myocardin is thought to contribute to heart hypertrophy as assessed in animal models. The aim of this study was to identify polymorphisms on the myocardin gene and investigate possible relationships with left ventricular structure in human hypertrophic cardiomyopathy (HCM). Eighty-four native Cretan individuals (36 patients with HCM and 48 healthy controls) were examined by direct sequencing and subsequent restriction fragment length polymorphism analysis and six polymorphisms were identified in the promoter region at positions -435T>C (rs758187), -629A>T (rs8071072), -1030C>G (rs1233851), -1069A>G, -1166A>G and -1406G>A (rs976906). Allele and haplotype frequencies were not significantly different between patients and controls. However, patients carrying the [-435C;-629T] allelic variant had decreased left ventricular wall thickness (LVWT, p = 0.020) and left ventricular mass (p = 0.006) as compared with the wild-type genotype. Carrier status of this myocardin promoter allelic variant was also associated with significant lower myocardin mRNA levels in peripheral blood (p = 0.039). Thus, a myocardin promoter allelic variant existing in the normal Cretan population was associated with decreased left ventricular mass in HCM patients and decreased myocardin mRNA levels in peripheral blood. Our results may be limited by the limited sample size, but are strengthened by the genetic homogeneity of the Cretan population. Our data suggest that functional natural myocardin promoter variation might be a genetic factor contributing to inter-individual differences in the development of cardiac hypertrophy.

Epidemiological characteristics, management and early outcome of acute myocardial infarction in Greece: the HELlenic Infarction Observation Study

INTRODUCTION

Taking into consideration the need for an updated survey on acute myocardial infarction (AMI) in Greece, we conducted the HELIOS study (HELlenic Infarction Observation Study), aiming to recruit a cohort of AMI patients that would be representative of the total AMI population.

METHODS

The HELIOS study is a countrywide registry of AMI, conducted during 2005-2006 by the Prevention Working Group of the Hellenic Cardiological Society. We enrolled 1840 AMI pts from 31 hospitals (mean age 68 +/- 13 years, 75% men, 1096 ST-elevation myocardial infarction [STEMI] patients), with a proportional representation of all types of hospitals and of all geographical areas. The study recruited 10% of the total number of AMI cases that occur per year on a countrywide basis, taking into consideration the seasonal variations of the population in each geographical area.

RESULTS

Despite demographic changes, there is still a male predominance among AMI patients and an increasing prevalence of cardiometabolic risk factors, (obesity, diabetes, hypertension) compared to previous AMI studies in the Greek population. Almost 60% of STEMI patients received reperfusion therapy, but the median value of the pain-to-door time was 180 minutes. The rates of administration of evidence-based medications during hospitalisation or upon discharge and the short-term mortality rates were in accordance with those observed in other international AMI registries.

CONCLUSIONS

The HELIOS study provided valuable insights into the epidemiology, clinical characteristics, management and outcome of patients with AMI in the Greek population. Although there are notable advances compared to previous reports, there is still considerable room for improvement and we should particularly focus on minimising the time delay between arrival at the emergency department and performance of reperfusion, by either pharmacological or catheter-based approaches.

Angiotensin II Type 1 Receptor Inhibition is Associated with Reduced Tachyarrhythmia-Induced Ventricular Interstitial Fibrosis in a Goat Atrial Fibrillation Model

BACKGROUND

Using a goat animal model, we tested the hypothesis that angiotensin-II inhibition reduces fibrotic degeneration of both the atrial and ventricular myocardium as well as AF induction susceptibility.

METHODS

We studied three groups of five goats over a 6-month period. The study animals in the first two groups were implanted with a pacemaker capable of maintaining AF with burst pacing. Additionally, in one group, goats were administered candesartan (AF+candesartan group). The third group (SR group) of animals served as control. Animals were tested for AF induction on day 0, 1, 30, 90 and 180. A "Vulnerability Index" (VI) for AF induction was calculated, defined as the ratio of total time in AF per number of bursts needed to induce sustained AF, in each session. At the end of the study, all four heart chambers were examined and fibrosis quantified.

RESULTS

Both AF goat groups developed cardiomegaly due to tachy-cardiomyopathy. Although, the VI was significantly increased in AF group over time (28.8+/-43 to 284.7+/-291, p=0.045), this was not the case for AF+candesartan group (30.3+/-40 to 170.8+/-243, p=0.23). Histology revealed a significant increase of fibrous tissue in goats with induced AF, noticeable in all four heart chambers, compared to controls. However, the degree of fibrosis was significantly lower in AF animals on candesartan.

CONCLUSIONS

Our study demonstrated a beneficial effect of angiotensin II inhibition on tachyarrhythmia-induced ventricular fibrosis. It is also consistent with previous studies indicating a reduction in burst-induced AF susceptibility in goats and confirms the favorable effects in atrial structural remodeling.

Acute coronary syndrome in an adult with anomalous origin of the left anterior descending coronary artery from the pulmonary trunk

Anomalous origin of the left anterior descending coronary artery is a very rare coronary vascular anomaly, especially in adults. We describe the case of a 45-year-old woman who presented with an acute coronary syndrome. Coronary angiography revealed an anomalous origin of the left anterior descending coronary artery from the main pulmonary trunk, with collateral filling from both the left circumflex and the right coronary artery. Treatment of choice of this coronary anomaly is usually surgical repair, while intense antithrombotic therapy should be considered, especially if the anomalous vessel is ectatic.

Reduced systemic inflammatory response to implantation of sirolimus-eluting stents in patients with stable coronary artery disease

Stent implantation causes significant injury to the vascular wall, resulting in inflammatory activation. Although sirolimus-eluting stents (SES) have anti-inflammatory properties, their effect on periprocedural systemic inflammatory response has not been sufficiently investigated. Eighty-one patients with stable coronary artery disease involving severe stenosis of one major epicardial coronary artery underwent coronary angioplasty with stent implantation and randomly received either SES or bare metal stents (BMS). Blood samples were taken 24h before, at 24h, 48 h and 1 month after the angioplasty and levels of high sensitive C-reactive protein (hsCRP), interleukin-6 (IL-6), interleukin-1 beta (IL-1 beta), and monocyte chemoattractant protein-1 (MCP-1) were determined. HsCRP after BMS implantation increased over 24h (p<0.001) and then remained steady, as did IL-6 and IL-1 beta similarly. In contrast, their levels in SES patients decreased to below baseline by the end of the month. MCP-1 levels increased by the end of 1 month (p<0.001) in the BMS group, whereas in SES they steadily decreased, becoming significantly lower than baseline from 48 h (p=0.015). In conclusion, patients with SES exhibit an attenuation of the postprocedural systemic inflammatory activation during a 1-month follow-up after stent implantation. This might partially explain the reduced restenosis rate associated with SES.

Arrhythmogenic right ventricular cardiomyopathy: echocardiographic and magnetic resonance imaging in a patient presenting with ventricular tachycardia

A 62-year-old man presented at our hospital with ventricular tachycardia. The diagnostic workup with echocardiography and magnetic resonance imaging that followed revealed a dilated, severely hypokinetic right ventricle with segmental wall dyskinesia suggesting the diagnosis of arrhythmogenic right ventricular cardiomyopathy. We present the echocardiographic and magnetic resonance imaging findings, including late enhanced magnetic resonance images.

Altered proximal aortic stiffness and endothelin plasma levels in diabetic patients with end-stage renal disease

Peripheral artery stiffness is altered in diabetic patients with end-stage renal disease (ESRD), whereas few data exist to confirm this trend for proximal aortic stiffness. The pulse wave velocity of the proximal aorta (PWVr) and of the carotid-to-femoral aortic segment (PWVcf) were determined by ultrasound imaging in 160 patients with ESRD (70 diabetic) and in 160 matched control subjects. Also, plasma levels of endothelin, homocysteine, and high-sensitivity C-reactive protein were determined in both groups. Patients with ESRD had increased pulse pressure, left ventricular (LV) end-diastolic diameter, LV mass index, PWVr, and PWVcf compared with control subjects (p < 0.05). Diabetic patients had increased LV mass index, PWVr, and PWVcf compared with nondiabetic patients with ESRD (p < 0.05). Endothelin levels exhibited a strong relation with PWVr (r = 0.32, p < 0.001) and PWVcf (r = 0.33, p < 0.001) measurements in ESRD patients. Multivariate linear regression analysis revealed that age, diabetes, and plasma levels of endothelin were major determinants of increased PWVr measurements in the total ESRD population. After adjustment for age, body surface area, time on dialysis, systolic blood pressure, history of hypertension, and plasma endothelin levels, diabetes was an independent factor associated with PWVr in ESRD subjects. Diabetic patients with ESRD had significantly increased proximal aortic stiffness and significantly altered plasma levels of endothelin as compared with the nondiabetic.

A comparative study of the efficacy and safety of procainamide versus propafenone versus amiodarone for the conversion of recent-onset atrial fibrillation

The appropriate treatment for the restoration of sinus rhythm in patients with atrial fibrillation (AF) of recent onset is still the subject of controversy. In this prospective, randomized, single-blind, placebo-controlled clinical study, we investigated the effectiveness and safety of procainamide, propafenone, and amiodarone, administered intravenously, for the conversion of recent-onset AF. We enrolled 362 consecutive patients (183 men; age 34 to 86 years; mean 65+/-10) with AF duration of no >48 hours. Of these patients, 89 were given procainamide, 91 propafenone, 92 amiodarone, and 90 placebo. Treatment was considered successful if conversion to sinus rhythm was achieved within the 24-hour study period. Baseline clinical characteristics were similar in the 4 groups. The treatment was successful in 61 of the 89 patients who received procainamide (68.53%; median time 3 hours), 73 of the 91 patients who received propafenone (80.21%; median time 1 hour), 82 of the 92 patients who received amiodarone (89.13%; median time 9 hours), and 55 of the 90 patients who received placebo (61.11%; median time 17 hours; p<0.05 for all medicated groups vs placebo; p<0.05 for amiodarone and propafenone vs procainamide). In conclusion, all 3 medications, when administered intravenously, are effective in the restoration of sinus rhythm in recent-onset AF. Amiodarone and propafenone are more effective whereas procainamide and propafenone are faster.

Endothelial cell function during atrial fibrillation and after restoration of sinus rhythm

Beat-to-beat variation in blood flow dynamics during atrial fibrillation (AF) has been associated with evidence of endothelial dysfunction. The aim of the present work is to confirm endothelial dysfunction in patients with AF and test the hypothesis that endothelial dysfunction is reversible upon restoration of normal sinus rhythm. Endothelium-dependent (flow-mediated dilation [FMD]) and endothelium-independent (nitroglycerin-mediated dilation [NMD]) vasodilator function of the brachial artery were measured using high-resolution ultrasound in 46 patients with persistent AF who were scheduled for internal electrical cardioversion and in 25 control subjects. In patients who remained in sinus rhythm after cardioversion, these measurements were repeated after 24 hours (n = 32) and 1 month (n = 19). Compared with control subjects, patients (n = 32) showed lower FMD during AF (8.1 +/- 3.6% vs 12.2 +/- 3.2%, respectively, p <0.001) and similar NMD (17.0 +/- 3.5% vs 15.9 +/- 3.1%, respectively, p = 0.21). In 19 patients who remained in sinus rhythm, FMD increased at both 24 hours (8.0 +/- 3.9% vs 10.6 +/- 4.6%, p = 0.015) and 1 month (8.0 +/- 3.9% vs 13.6 +/- 5.3%, p <0.001). In contrast, NMD was not significantly altered at 24 hours or 1 month after sinus rhythm restoration (17.1 +/- 3.9% vs 17.2 +/- 4.0% vs 16.9 +/- 4.1%). In conclusion, AF is associated with impairment in endothelial function that improves after sinus rhythm restoration.

Effect of inhaled salbutamol on coronary circulation in humans

In 12 patients we assessed the effect of inhaled salbutamol on the coronary circulation. According to our results, large doses of salbutamol increase coronary flow, but not in proportion to the needs of the myocardium (as documented by the increase in coronary oxygen extraction), and decrease coronary flow reserve. These effects may have deleterious consequences in patients with coronary artery disease, causing or worsening myocardial ischemia.

Combined use of aspiration catheter and distal embolisation protection device to facilitate angioplasty of a totally occluded saphenous vein graft

Angioplasty of totally occluded saphenous vein grafts is a very challenging procedure and the likelihood of distal embolisation and no-reflow is much higher than in any conventional angioplasty. The use of thrombus aspiration and distal protection devices, although not well studied in a large number of patients, has been shown to be quite effective in preventing such complications. In this case we report our satisfactory experience from the combined use of a novel aspiration catheter and a distal protection device for the treatment of a totally occluded saphenous vein graft.

Relation of Proximal Aorta Stiffness to Left Ventricular Diastolic Function in Patients with End-Stage Renal Disease

AIM

We examined the relationship between proximal aortic stiffness and left ventricular (LV) diastolic function in patients with end-stage renal disease (ESRD).

PATIENTS AND METHODS

We studied 99 patients with ESRD with preserved LV ejection fraction greater than 50% and 83 controls. We assessed the aorta stiffness by measuring the pulse wave velocity (PWV) in the proximal aorta (PWVr) using a novel echo application and in the descending aorta (PWVcf) using a foot-to-foot method. Patients were classified according to LV diastolic filling pattern into normal, delayed relaxation, pseudonormal, and restrictive filing pattern groups.

RESULTS

Patients with ESRD had increased PWVr, PWVcf, and LV mass index (LVMI) compared with controls (all P < .0001). Patients with advanced diastolic dysfunction showed increased PWVr (P < .001) and PWVcf (P = .007) compared with those with mild diastolic dysfunction. PWVr was correlated to PWVcf (r = 0.74, P < .001) in patients with ESRD. Multivariate linear regression analysis revealed that PWVr was independently correlated to both LVMI and LV diastolic filling pattern.

CONCLUSIONS

Increased LVMI, advanced LV diastolic dysfunction, and generalized aortic stiffening were observed in patients with ESRD. Proximal aorta stiffness is associated with both increased LVMI and advanced LV diastolic dysfunction in those patients.

Achievement of pulmonary vein isolation in patients undergoing circumferential pulmonary vein ablation: a randomized comparison between two different isolation approaches

INTRODUCTION

Circumferential pulmonary vein ablation (CPVA) with the endpoint of pulmonary vein (PV) isolation has been developed as an effective therapy for atrial fibrillation (AF). This endpoint can be achieved either by closing gaps along circular lines or by segmental PV isolation inside the circular lines after creation of initial CPVA lesions. We investigated whether the clinical outcome depends on the PV isolation approach used during the first-time CPVA procedure.

METHODS AND RESULTS

One hundred consecutive patients (69 male; age, 56.7 +/- 11.6 years) who underwent first-time CPVA for treatment of symptomatic AF were enrolled. PV isolation was randomly achieved either by CPVA alone (aggressive CPVA [A-CPVA] group, n = 50) or by a combination of CPVA with segmental PV ostia ablation (modified CPVA [M-CPVA] group, n = 50). Recurrence of atrial tachyarrhythmias (ATa) within 3 months after the initial procedure occurred in 30 patients (60%) in the M-CPVA group and in only 15 patients (30%) in the A-CPVA group (P < 0.01). ATa relapse after the first 3 months was detected in 21 patients (42%) in the M-CPVA group, compared with 9 patients (18%) in the A-CPVA group (P = 0.01). At 13 +/- 4 months, patients treated by the A-CPVA approach had greater freedom from ATa recurrence than patients who underwent M-CPVA (P = 0.01). The M-CPVA approach was the only independent predictor associated with procedural failure (RR 0.318; 95% CI 0.123-0.821; P = 0.02).

CONCLUSIONS

When PV isolation is the endpoint of CPVA, the efficacy of the A-CPVA approach is better than that of M-CPVA.

Gender-related differences in presentation, treatment, and outcome of patients with atrial fibrillation in Europe: a report from the Euro Heart Survey on Atrial Fibrillation

OBJECTIVES

This study sought to investigate gender-related differences in patients with atrial fibrillation (AF) in Europe.

BACKGROUND

Gender-related differences may play a significant role in AF.

METHODS

We analyzed the data of 5,333 patients (42% female) enrolled in the Euro Heart Survey on Atrial Fibrillation.

RESULTS

Compared with men, the women were older, had a lower quality of life (QoL), had more comorbidities, more often had heart failure (HF) with preserved left ventricular systolic function (18% vs. 7%, p < 0.001), and less often had HF with systolic dysfunction (17% vs. 26%, p < 0.001). Among patients with typical AF symptoms (56% of women, 49% of men), there was no gender-related difference in the choice of rate or rhythm control. Among patients with atypical or no symptoms (44% of women, 51% of men), women less frequently underwent rhythm control (39% vs. 51%, p < 0.001) than did men. Women underwent less electrical cardioversion (22% vs. 28%, p < 0.001). Prescription of oral anticoagulants was identical (65%) in both genders. One-year outcome was similar except that women had a higher chance for stroke (odds ratio 1.83 in multivariable regression analysis, p = 0.019).

CONCLUSIONS

Women with AF had more comorbidities, more HF with preserved systolic function, and a lower QoL than men. In the large group with atypical or no symptoms, women were treated appropriately more conservatively with less rhythm control than men. Women had a higher chance for stroke. Long-term QoL changes and other morbidities and mortality were similar.

Androgen deficiency and endothelial dysfunction in men with end-stage kidney disease receiving maintenance hemodialysis

OBJECTIVES AND METHODS

Two thirds of men with end-stage kidney disease (ESKD) have serum testosterone levels in the hypogonadal range. We examined if low serum testosterone levels were correlated with measures of endothelial dysfunction in ESKD. Bilateral common carotid artery (CCA) intima-media thickness (IMT) and atherosclerotic plaque occurrence, left ventricular mass index, flow- (FMD) and nitrate-mediated vasodilatation (NMD) of the brachial artery were determined by ultrasound imaging in 100 nondiabetic men with ESKD (50 men exhibited androgen deficiency; serum testosterone concentrations <300 ng/dl).

RESULTS

Left-ventricular mass index, CCA diameter, CCA-IMT and atherosclerotic plaque occurrence were all significantly increased in ESKD patients with androgen deficiency compared with patients without androgen deficiency (p < 0.05). Also, FMD and NMD measurements were significantly reduced in the former compared with the latter (p < 0.05). Testosterone levels were inversely correlated with age and duration of hemodialysis therapy (r = -0.44 and r = -0.55; p < 0.001). Testosterone levels were negatively correlated to CCA-IMT and atherosclerotic plaque occurrence in patients with androgen deficiency (r = -0.32, p < 0.003, and r = -0.23, p < 0.04, respectively). FMD and NMD measurements were positively correlated to total (r = 0.65 and r = 0.61; both p < 0.0001) and free (r = 0.52 and r = 0.48; both p < 0.001) testosterone levels in patients with low androgenicity.

CONCLUSION

The present results indicated that ESKD patients with androgen deficiency had increased CCA-IMT, atherosclerotic plaque occurrence and reduced FMD and NMD compared with patients without androgen deficiency. Testosterone serum levels were negatively correlated to CCA-IMT and positively correlated to endothelium-dependent vasodilatation in ESKD patients with androgen deficiency.

Clarithromycin treatment and QT prolongation in childhood

The effect of clarithromycin on the QT interval was studied in a group of 28 children treated for respiratory tract infections. QTc was measured before and following 24 h of treatment. A modest (average 22 ms, 95% CI 14-30 ms) but significant QTc prolongation (p<0.001) was observed, with seven cases having a QTc >440 ms during treatment (including a single case with QTc >460 ms).

CONCLUSION

Serial QTc measurements are necessary for early detection of children at risk for drug-induced arrhythmias.