Relationship between left atrial functions, P-terminal force and interatrial block in chronic haemodialysis patients

OBJECTIVE

Interatrial block (IAB) connotes a P wave duration ≥ 110 msec on electrocardiography (ECG). P-terminal force corresponds to a biphasic P wave with its terminal negative phase ≥ 40 msec x mm in V1 derivation on ECG. IAB and P-terminal force are closely related parameters and they are accepted as predictors for left atrial dysfunction, left atrial dilatation, atrial fibrillation and strokes. Left atrial functions in chronic haemodialysis patients becomes worse in the course of time because of long standing pressure and volume overload. The aim of this study is to evaluate the relationship between IAB, P-terminal force and left atrial functions.

PATIENTS AND METHODS

68 chronic haemodialysis patients and 60 control subjects were included in the study. Conventional echocardiography and left atrial dynamic functions were measured in all cases. The subjects with IAB and P-terminal force on ECG were identified.

RESULTS

Left ventricular size, wall thickness and left atrial diameters were significantly greater in haemodialysis patients than the control group (p < 0.001). 42 (62%) patients had IAB (≥ 110 msec) and 45 (66%) patients had P-terminal force ( ≥ 40 msec x mm) in the haemodialysis group. Left atrial reservoir, conduit and pump functions were significantly lower in the haemodialysis group than the control group (p < 0.001). There was a statistically significant correlation between left atrial functions, IAB (≥ 110 msec) and P-terminal force (≥ 40msec x mm) in all parameters (p < 0.001).

CONCLUSIONS

This study showed that decreased left atrial functions in chronic haemodialysis patients are closely correlated with IAB and P-terminal force.

Comparison of effects of nebivolol, carvedilol and irbesartan on left ventricular hypertrophy associated with hypertension

OBJECTIVES

The aim of this study was to investigate if the new generation beta-blockers are as effective as irbesartan, which is an angiotensin receptor blocker (ARB), on left ventricular hypertrophy (LVH).

PATIENTS AND METHODS

The study included 85 patients (average age: 56.6±9.6 year) with stage 1 and 2 hypertension, who previously didn't receive an antihypertensive treatment, but diagnosed with LVH echocardiographically. The patients were divided into three different treatment groups: irbesartan (n=28), nebivolol (n=25) and carvedilol (n=32). The patients were reassessed clinically and echocardiographically at 3, 6 and 12 months after the treatments.

RESULTS

There was no statistically significant difference in baseline left ventricular mass index (LVMI) and other parameters among the three treatment groups (p > 0.05). Although there was no significant decrease in LVMI in irbesartan and carvedilol groups at 3 months after the treatment (p > 0.05), the values measured at 6 and 12 months (p < 0.0001) were significant. The decrease in LVMI in the nebivolol group was significant at 3, 6 and 12 months (p < 0.0001). There was a significant difference in measurements at 12 months (p < 0.05).

CONCLUSIONS

Both of the new generation beta-blockers were more effective than irbesartan in the regression of LVH. A significant regression in LVH was observed 3 months after nebivolol treatment and 6 months after irbesartan and carvedilol treatments.

Predictors of reintervention after coronary artery bypass grafting

AIM

Percutaneous and surgical reintervention after coronary artery bypass grafting (CABG) is frequent. The purpose of this study was to determine the predictors of reintervention in patients with symptoms of recurrent ischemia after coronary artery bypass graft surgery (CABG).

PATIENTS AND METHODS

The data of 20000 patients who had coronary angiography (CAG) from 2003 to 2010 in our centre were retrospectively analysed. 485 of these patients with CABG who had CAG were included in this study. Demographic characteristics, the presence of coronary artery disease (CAD), risk factors for CAD, electrocardiographic (ECG) changes, troponin and CKMB levels, and left ventricular function were evaluated in terms of time elapsed after CABG.

RESULTS

Reintervention was performed significantly more frequent in patients with acute coronary syndrome, diabetes mellitus (DM), hypertension (HT), family history of CAD, ECG changes, positive troponin level, elevated CKMB, ejection fraction (EF) > 50% and in smoker patients (p < 0.05). Multivariate backward logistic regression analysis revealed that DM, smoking, family history of CAD, HT, ECG changes and patients with EF > 50% were found the independent predictors of reintervention.

CONCLUSIONS

Reintervention after CABG is especially higher in patients with risk factors for atherosclerosis and those who have ECG changes and normal EF. Knowledge of these risk factors is useful in the determination of CAG requirement and modification of risk factors for  atherosclerosis may play an important role in reducing reintervention.