Distinguishing Right Ventricular Cardiomyopathy From Idiopathic Right Ventricular Outflow Tract Tachycardia with T-wave Alternans.

BACKGROUND: The 2 predominant etiologies of right ventricular tachycardia (VT) are arrhythmogenic right ventricular cardiomyopathy (ARVC) and idiopathic VT arising from the right ventricular outflow tract. Discrimination between these 2 entities is critical, as their prognoses and therapeutic options differ. The microvolt T-wave alternans (TWA) is widely used to predict lethal ventricular arrhythmias in various diseases. However, the clinical significance of TWA in patients with VT originating from the right ventricle has been unknown. This study aims to investigate the possible role of TWA to discriminate ARVC from idiopathic right ventricular outflow tract tachycardia (RVOT-VT). METHODS: This study enrolled 38 patients (23 male, 43 ± 16 years) with VT originating from the right ventricle. TWA was measured during exercise testing using the modified moving average method. TWA results were compared among patients with ARVC and RVOT-VT. RESULTS: Twenty-five patients (16 male, 42 ± 16 years) met the Task Force criteria for the diagnosis of ARVC, and 13 patients (7 male, 45 ± 14 years) had idiopathic RVOT-VT. Twenty patients with ARVC had positive TWA test, whereas only 1 patient with RVOT-VT had (80% versus 8%, P < 0.001). CONCLUSIONS: In patients with VT of right ventricle origin, positive TWA test supports the diagnosis of ARVC.

The Relationship between Left Atrial Volume and Ventricular Arrhythmias in the Patients with Dilated Cardiomyopathy.

BACKGROUND: The present study aimed to investigate the relationship between Left Atrial Volume (LAV), a marker of diastolic dysfunction, and the frequency of malignant ventricular arrhythmia in the patients with left ventricular dysfunction and a previously implanted Implantable Cardioverter Defibrillator (ICD) device. METHODS: This cross-sectional study was conducted on 32 patients with ischemic or idiopathic dilated cardiomyopathy, each having had an ICD device implanted at least 1 year beforehand. The ventricular arrhythmia episodes which were detected and stored by the device were retrieved and evaluated. In addition to routine echocardiographic measurements, all the patients had their LAV and LAV indexes calculated. After all, student's t-test, Mann-Whitney U test, and Pearson correlation were used to analyze the data. Besides, P value < 0.05 was considered as statistically significant. RESULTS: This study was conducted on 4 female and 28 male patients with the mean age of 58.41 ± 9.97 years. Among the study patients, 21 had at least one previous myocardial infarction. In addition, 17 patients had experienced sustained VT or VF within the last year. No significant difference was found between the patients with and without malignant ventricular arrhythmias (sustained VT or VF) regarding LAV (17 patients with arrhythmia (68 + 23.39 mL) vs. 15 patients without arrhythmia (55.13 ± 20.41 mL); P = 0.100). However, the LAV index was significantly higher in the patients with arrhythmia compared to those without arrhythmia (39.27 ± 12.19 mL / m2 vs. 25.18 ± 7.45 mL / m2; P = 0.004). Both LAV (73.33 ± 17.64 mL and 57.52 ± 23.15 mL, respectively; P = 0.040) and LAV index (40.86 ± 8.47 mL / m2 and 28.20 ± 11.77 mL / m2, respectively; P = 0.010) were significantly greater in the patients with ICD shock therapy within the last year compared to the others. However, both groups were similar regarding Left Ventricular Volume (LVV), LVV index, and ejection fraction. CONCLUSIONS: The study findings demonstrated that LAV and LAV index could be used in detecting the patients who are at high risk of malignant ventricular arrhythmias.

Cholesteryl ester transfer protein Taq1B polymorphism in an angiographically assessed Turkish population: no effects on coronary artery disease risk.

BACKGROUND: Taq1B polymorphism of cholesteryl ester transfer protein (CETP) is believed to associate with high-density lipoprotein-cholesterol (HDL-C) levels and may alter the susceptibility to atherosclerosis. AIM OF THE STUDY: This study investigated the effects of Taq1B polymorphism on HDL-C and coronary artery disease (CAD) risk in angiographically defined CAD patients. METHODS: One hundred thirty-five CAD patients and 112 healthy controls were screened for the CETP Taq1B genotype and plasma lipids. RESULTS: The genotype frequency of CAD patients and controls were similar. The HDL-C levels of all genotypes in the CAD group were significantly lower than the corresponding controls. Smoking and plasma triglycerides were the predictors of the HDL-C level in B1B1 bearers, whereas the subjects with a polymorphic B2 allele were affected by smoking and sex. CONCLUSION: CETP Taq1B polymorphism neither plays a role in determining HDL-C levels nor is a useful predictor of the risk of CAD.

The association of P-selectin glycoprotein ligand-1 VNTR polymorphisms with coronary stent restenosis.

BACKGROUND: P-selectin and P-selectin glycoprotein ligand-1 (PSGL-1) regulate the initial interactions between leukocytes, activated platelets and endothelial cells. Recently, a variable number of tandem repeats (VNTR) polymorphism in PSGL-1 gene affecting the length of the extracellular domain of PSGL-1 and the distance of the P-selectin binding site to the cell surface has been described. There are limited numbers of studies reporting PSGL-1 polymorphism might affect the inflammatory response and thrombosis. We explored the association between PSGL-1 VNTR polymorphisms (especially AB genotype that has the most deformed configuration of the binding site) and the development of coronary stent restenosis and stent thrombosis in patients with coronary artery disease (CAD). MATERIALS AND METHODS: Eighty-seven patients with in-stent restenosis and 93 patients with patent coronary stents were included into the study. The distributions of age, gender, hypertension, diabetes, smoking, total cholesterol and triglyceride levels were similar between the groups. Genomic DNAs were obtained by standard methods from whole blood samples. Specific primers were used to amplify PSGL-1 gene by polymerase chain reaction (PCR). RESULTS: Three alleles and 5 different genotypes were detected. In the in-stent restenosis group; allele frequencies were 79.5% for A allele, 18.1% for B allele and 2.4% for C allele and in the patent stent group; allele frequencies were 79.3% for A allele, 20.1% for B allele and 0.6% for C allele. The allele frequencies were similar between the in-stent restenosis group and patent stent group (P = 0.97 for A allele, P = 0.73 for B allele and P = 0.19 for C allele). Genotype distributions were also similar between the groups. There were not any significant associations between PSGL-1 AB genotype and stent restenosis (31.3% vs. 27.2%, P = 0.54), repetitive stent restenosis (33.3% vs. 28.8%, P = 0.82) or in-stent thrombosis (44.4% vs. 28.2%, P = 0.37). In neither male patients nor female patients, there was any significant association between AB genotype and restenosis (32.2% vs. 24.3% P = 0.31 and 29.2% vs. 38.9% P = 0.51, respectively). However, among patients with a family history of early CAD, significantly higher percentage of AB genotype was found in those with stent restenosis (41.4% vs. 18.8%, P = 0.03). CONCLUSIONS: No significant association was found between PSGL-1 VNTR polymorphisms and in-stent restenosis. However, in patients with a family history of early CAD presence of PSGL-1 AB genotype might increase the risk of in-stent restenosis.

Association of haematological indices with the degree of microvascular injury in patients with acute anterior wall myocardial infarction treated with primary percutaneous coronary intervention.

BACKGROUND: In acute myocardial infarction (AMI), increased neutrophil count has been associated with more severe coronary artery disease and larger infarct size. Increased mean platelet volume (MPV) is also associated with poor clinical outcome and impaired angiographic reperfusion in patients with AMI. However, the associations of neutrophil count and MPV with the indices of tissue level reperfusion were not fully elucidated. AIM: To elucidate the relationship between baseline neutrophil count and MPV on presentation and microvascular injury in patients with anterior AMI treated with primary percutaneous coronary intervention (pPCI). METHODS: 41 patients with anterior wall AMI treated successfully with pPCI were included. The leucocyte count, neutrophil count and MPV were obtained on admission, and the percentage of neutrophils was calculated. After PCI thrombolysis in myocardial infarction, grade 3 flow was established in all patients. The coronary flow velocity pattern (diastolic deceleration time (DDT)) was examined with transthoracic echocardiography and measured intracoronary pressures with fibreoptic pressure-temperature sensor-tipped guidewire in the left anterior descending artery within 48 h after pPCI. Thermodilution-derived coronary flow reserve (CFR) was calculated. Index of microvascular resistance (IMR) was defined as simultaneously measured distal coronary pressure divided by the inverse of the thermodilution-derived hyperaemic mean transit time. Subsequently, a short compliant balloon was placed in the stented segment and inflated to measure coronary wedge pressure (CWP). RESULTS: Higher neutrophil counts were strongly associated with higher IMR (r = 0.86, p<0.001), lower CFR (r = -0.60, p<0.001), shorter DDT (r = -0.73, p<0.001) and higher CWP (r = 0.73, p<0.001). Likewise, there were significant correlations among the percentage of neutrophils and CFR (r = -0.34, p = 0.02), IMR (r = 0.46, p = 0.002), DDT (r = -0.36, p = 0.01) and CWP (r = 0.49, p = 0.001). Relationships among leucocyte count and IMR (r = 0.38, p = 0.01), CFR (r = -0.33, p = 0.03), DDT (r = -0.36, p = 0.01) and CWP (r = 0.32, p = 0.026) were slightly significant. Higher neutrophil count remained independently associated with indices of microvascular perfusion in multivariable models controlling for age, smoking habits and time to treatment. Also, higher MPV on admission was strongly associated with higher IMR (r = 0.89, p<0.001), steeper DDT (r = -0.64, p<0.001), lower CFR (r = -0.43, p = 0.004) and higher CWP (r = 0.77, p<0.001). CONCLUSION: Absolute and relative neutrophilia and higher MPV on admission were independently associated with impaired microvascular perfusion in patients with anterior AMI treated with pPCI. It is possible that neutrophilia and high MPV are simple surrogate markers of worse microvascular injury in patients with AMI.