Advanced Age, Female Gender and Delay in Pacemaker Implantation May Cause TdP in Patients With Complete Atrioventricular Block

AIM

We aimed to report the clinical features related to torsades de pointes (TdP) in patients with complete AV block (CAVB).

METHODS

Patients with CAVB who were admitted to our instituition between January 2007 and January 2010 were retrospectively evaluated in terms of the occurence of TdP. The clinical features were compared in patients with and without TdP using the software of SPSS.

RESULTS

Sixty-four patients were determined to have CAVB. Three of them had documented episodes of TdP. All three patients experiencing TdP were females, whereas 48% of the patients with CAVB were females. The mean age of patients with TdP was significantly greater than the mean age of the other patients (85 ±3 vs. 78±7.6, respectively; p<0.05). In our archives, bradycardia exposure time could be determined in only 49 patients without TdP. Among them, just 10 patients had been exposed to bradycardia over 48 hours, whereas all of the 3 patients with TdP had been exposed to bradycardia over 48 hours (p<0.05). Additionally, in two patients with TdP, we demonstrated that QT and QTc prolongation increases as the duration of bradycardia is extended. Furthermore, all patients with TdP had notched T waves in the ECG on the occurrence day of TdP, whereas they did not have any notched T wave in their ECG on the admission day.

CONCLUSION

Among the patients with CAVB, elderly females are more susceptible to development of TdP. Delay in institution of physiological heart rate leads to further QT prolongation and thereby to TdP. Besides QT prolongation, the finding of T wave notching on ECG may also have a predictive value for TdP.

ST elevation in the lead aVR during exercise treadmill testing may indicate left main coronary artery disease

BACKGROUND

exercise treadmill testing (ETT) is the most widely used method for evaluating patients with coronary artery disease. Predicting the left main coronary artery (LMCA) disease before invasive procedures is very important in risk assessment because of its severe clinical outcome.

AIM

To examine whether ST elevation in lead aVR during ETT may suggest LMCA disease since the lead aVR is the reciprocal lead of LMCA.

METHODS

in this study, 61 patients with positive ETT were included. The study group consisted of 21 patients with ST elevation in lead aVR. Forty patients, also having positive ETT, but without ST elevation in lead aVR comprised the control group. All patients underwent coronary angiography.

RESULTS

coronary angiography in the study group revealed significant LMCA stenosis in 16 (76%) patients, whereas LMCA disease was present in only 3 (8%) patients from the control group. There was no significant coronary artery stenosis in 5 patients in the study group and 12 patients in the control group. Of the 16 patients who had LMCA stenosis, 9 had isolated LMCA disease and 7 had additional stenotic lesions in LAD or circumflex coronary arteries. The sensitivity and specificity of ST segment elevation in lead aVR during ETT was 84% and 88%, respectively. The values of positive and negative predictive value of this finding in diagnosing the presence of LMCA were 76% and 93%, respectively.

CONCLUSIONS

ST segment elevation in lead aVR during ETT may point to a high probability of the presence of LMCA disease.

Increased P wave dispersion in patients with liver steatosis

AIM

Hepatic steatosis is associated with metabolic and hemodynamic abnormalities induced by insulin resistance and inflammatory state. Since abnormalities of P wave dispersion may be accompanied with latter issues we evaluated this subject in patients with hepatic steatosis.

METHODS

Total of 106 patients and 56 healthy subjects were enrolled and performed hepatic ultrasonography, echocardiography, electrocardiogram, and biochemistry tests. Clinical features, laboratory and echocardiographic parameters, P wave dispersion were compared between groups and analyzed for any correlation among parameters.

RESULTS

Body mass index (BMI), waist circumference, systolic and diastolic blood pressure, levels of total and LDL cholesterol, and fasting blood glucose (FBG), and left atrial diameter were significantly higher in patients with hepatic steatosis. Peak velocities of mitral E and A waves and their ratio were abnormally changed in patients compared to normals. In multiple linear regression analysis, approximately all of the variables previously correlated within Pearsons' correlation test were found to be significantly correlated with P wave dispersion [ waist circumference (ß=0.151, p=0.048), LDL cholesterol (ß=0.234, p=0.000), FBG (ß=0.402, p= 0.000), alanine aminotransferase (ALT) (ß=0.205, p= 0.006), alkaline phosphatase (ALP) (ß=0.277, p=0.000), γ-glutamyl transferase (γ-GT) (ß=0.240, p=0.000), left atrial diameter (ß=0.204, p=0.003), heart rate (ß=0.123, p=0.037)].

CONCLUSIONS

Increased P wave dispersion may indicate a risk of atrial arrhythmia which may be complicated with disabling symptoms and thromboembolism in patients with hepatic steatosis. Consequently, hepatic steatosis is associated with increased risk for cardiovascular disease due to metabolic and hemodynamic abnormalities probably induced by insulin resistance and inflammaory state.