The Effects of Female Sex Hormones on Ventricular Premature Beats and Repolarization Parameters in Physiological Menstrual Cycle.

BACKGROUND: The effects of gender difference on cardiac electrophysiology have been well studied. In this study, we aimed to evaluate the effects of estradiol and progesteron changes occuring in physiological menstrual cycle on ventricular premature beats (VPBs) and cardiac repolarization parameters. METHODS: Women of reproductive age with VPBs were included into the study group and healthy women were recruited as the control group. During the menstruation period, a 12-lead electrocardiography, blood samples, and 24-hour rhythm Holter were applied to the study group. Similarly, all tests were repeated in the estimated ovulation period (12-14 days before menstruation) by all cases. RESULTS: The study group consisted of 20 women patients with VPB, and the control group of 18 healthy women. While the number of VPB in the menstruation period was 210 beats/day (interquartile range [IQR]: 1,144), it decreased to 86 beats/day (IQR: 251) in the ovulation period with statistical significance (P < 0.05). Average heart rate in the menstruation period was 81.4 ± 10 beats/min and it significantly increased to 84.6 ± 8 beats/min in the ovulation period (P < 0.05). There were no differences in cardiac repolarization parameters in both menstruation and ovulation periods between the study and control groups. Comparing the menstruation and the ovulation periods, J-Tpeak interval, which reflects early repolarization, was shorter in the ovulation period (193 ± 27.7 ms and 201.1 ± 28.6 ms, respectively; P < 0.05). Other repolarization parameters did not show any significant difference. CONCLUSION: VPB frequency decreases with estradiol peak in the ovulation period. This suggests that estrogen may have protective effects against ventricular arrhythmias.

[Radiofrequency catheter ablation of idiopathic ventricular tachycardia originating from the mitral annulus]. / Mitral aniilüs kaynakli idiyopatik ventrikül tasikardisinde radyofrekans kateter ablasyonu.

Idiopathic ventricular tachycardias (VT) originate mostly from the right ventricular outflow tract and rarely from the mitral annulus. Herein, we present a 20-year-old male patient in whom we performed a successful radiofrequency catheter ablation of mitral annular VT. He admitted to our department with the complaints of palpitations and shortness of breath attacks for 5 years. Detailed assessment disclosed idiopathic VT which subsequently was found to be derived from the mitral annulus in electrophysiologic study. The patient's symptoms disappeared after successful RF ablation and the follow-up Holter ECG was totally normal.

Neurological symptoms after a provocative dive: spinal DCS or anterior spinal artery syndrome?

Reported here is a 37-yr-old professional diving instructor who had developed complaints of back pain and weakness in the lower extremities after diving. He was eventually diagnosed as having spinal cord decompression sickness along with a likely diagnosis of anterior spinal artery (artery of Adamkiewicz) syndrome. Additionally, since the transthoracic echocardiography revealed patent foramen ovale, we hypothesized that it might have been a potential route for gas bubbles to occlude the anterior spinal artery in this diver.

N-terminal pro-B-type natriuretic peptide levels increases after hyperbaric oxygen therapy in diabetic patients.

PURPOSE: Diabetic patients receive hyperbaric oxygen therapy for non-healing lower extremity ulcers. Exposure to hyperbaric hyperoxia during hyperbaric oxygen therapy may affect cardiovascular functions by different mechanisms. Patients may experience serious problems such as pulmonary edema and death during hyperbaric oxygen therapy. The effect of hyperbaric oxygen therapy on cardiovascular functions in diabetic patients is not well documented. N-terminal pro-B-type natriuretic peptide (NT-proBNP) has been suggested as powerful biochemical marker of cardiac function. The aim of this study was to investigate the effect of hyperbaric oxygen therapy on NT-proBNP levels in diabetic patients. METHODS: Twenty-five diabetic patients (19 male and 6 female, 64.7 +/- 10.2 yr), who were planning to undergo hyperbaric oxygen therapy for non-healing lower extremity ulcers, were prospectively enrolled into the study. All patients were evaluated with echocardiography before the study. Heart rate and arterial blood pressure of patients were measured, and venous blood samples were drawn from each patient for NT-proBNP analysis before and immediately after the hyperbaric oxygen therapy. RESULTS: NT-proBNP levels increased from 815 +/- 1096 pg/ml to 915 +/- 1191 pg/ml after HBO2 therapy (P < 0.05). Heart rate and arterial blood pressure did not change with HBO2 therapy (P > 0.05). CONCLUSION: Hyperbaric oxygen therapy induces considerable ventricular wall stress in diabetic patients. Care should be taken when a diabetic patient with cardiovascular disease is treated with hyperbaric oxygen therapy.

Hyperbaric oxygen therapy decreases QT dispersion in diabetic patients.

Diabetes mellitus is frequently associated with the malignant ventricular arrhythmias and sudden death. The QT dispersion is the difference between the longest and shortest QT interval calculated from the standard 12-lead electrocardiogram. The QT dispersion is suggested as an index of myocardial electrical activity. An increase in QT dispersion is associated with the malignant ventricular arrhythmias and sudden cardiac death. Diabetic patients receive hyperbaric oxygen (HBO) therapy for non-healing lower extremity ulcers. The aim of this study was to determine the effect of HBO therapy on QT dispersion in diabetic patients. Thirty diabetic patients (18 male and 12 female, 59.9 +/- 10 years), who were planning to undergo ten sessions of HBO therapy in two weeks for non-healing lower extremity ulcers, were consecutively enrolled into the study. The 12-lead resting electrocardiography recordings were taken before the first HBO therapy and after the 10th HBO-therapy session. QT intervals were measured on electrocardiogram. QT intervals were corrected for heart rate by using Bazett's formula (corrected QT [QTc] = QT/ radical R - R [seconds]). QTc dispersion was significantly decreased from 59.8 +/- 17.4 msec to 52.2 +/- 15.5 msec after ten sessions of HBO therapy (p < 0.05). However, maximum QTc, minimum QTc and mean QTc did not change significantly after HBO therapy. We have concluded that HBO therapy may reduce the risk of malignant ventricular arrhythmia and sudden cardiac death in diabetic patients when applied repetitively.

Hyperbaric oxygen therapy improves myocardial diastolic function in diabetic patients.

Myocardial diastolic dysfunction is the relaxation abnormality of ventricles that limits the diastolic filling and generally precedes diastolic heart failure. Diastolic dysfunction is a common finding in diabetes. Diabetic patients receive hyperbaric oxygen (HBO) therapy for non-healing lower extremity ulcers, and exposure to HBO therapy is known to influence cardiovascular functions. This study was designed to evaluate the effect of HBO therapy on myocardial diastolic function in diabetic patients. Thirty diabetic patients (18 male and 12 female, 59.9 +/- 10 years old), who were planning to undergo HBO therapy, were consecutively enrolled. Myocardial diastolic function was evaluated by pulsed wave Doppler echocardiography and tissue Doppler echocardiography before the first HBO therapy and after the tenth HBO therapy session. HBO therapy improved the relaxation capability of left ventricular myocardium, which was reflected by reduction in E wave deceleration time of mitral valve inflow (286.1 +/- 65.8 msec vs 214.3 +/- 32.1 msec, p < 0.05). HBO therapy also affected favorably the diastolic filling dynamics of right ventricle, which was partially reflected by the changes in E wave peak velocity of tricuspid valve inflow (0.48 +/- 0.07 m/sec vs 0.46 +/- 0.09 m/sec, p < 0.05). Tissue Doppler parameters of mitral lateral annulus, which are better correlated with ventricular relaxation, tended to be improved after HBO therapy, but the degree of improvement was not statistically significant. In conclusion, we suggest that HBO therapy may improve the myocardial diastolic function of diabetic patients when applied repetitively.