Skin sympathetic nerve activity and ventricular arrhythmias in acute coronary syndrome.

BACKGROUND: Acute coronary syndrome (ACS) is major cause of ventricular arrhythmias (VAs) and sudden death. neuECG is a noninvasive method to simultaneously record skin sympathetic nerve activity (SKNA) and electrocardiogram. OBJECTIVE: The purpose of this study was to test the hypotheses that (1) ACS increases average SKNA (aSKNA), (2) the magnitude of aSKNA elevation is associated with VAs during ACS, and (3) there is a gender difference in aSKNA between patients without and with ACS. METHODS: We prospectively studied 128 ACS and 165 control participants. The neuECG was recorded with electrodes at Lead I configuration at baseline, during mental math stress, and during recovery (5 minutes for each phase). All recordings were done in the morning. RESULTS: In the control group, women have higher aSKNA than do men at baseline (0.82 ± 0.25 µV vs 0.73 ± 0.20 µV; P = .009) but not during mental stress (1.21 ± 0.36 µV vs 1.16 ± 0.36 µV; P = .394), suggesting women had lower sympathetic reserve. In comparison, ACS is associated with equally elevated aSKNA in women vs men at baseline (1.14 ± 0.33 µV vs 1.04 ± 0.35 µV; P = .531), during mental stress (1.46 ± 0.32 µV vs 1.33 ± 0.37 µV; P = .113), and during recovery (1.30 ± 0.33 µV vs 1.11 ± 0.30 µV; P = .075). After adjusting for age and gender, the adjusted odds ratio for VAs including ventricular tachycardia and ventricular fibrillation is 1.23 (95% confidence interval 1.05-1.44) for each 0.1 µV aSKNA elevation. aSKNA is positively correlated with plasma norepinephrine level. CONCLUSION: ACS is associated with elevated aSKNA, and the magnitude of aSKNA elevation is associated with the occurrence of VAs. Women have higher aSKNA and lower SKNA reserve than do men among controls but not among patients with ACS.

Diffuse ST-Segment Depression with ST-Segment Elevation in Lead aVR in 12-Lead Electrocardiography May Indicate Ischemic Change of Severe Aortic Stenosis.

UNLABELLED: Diffuse ST-segment depression with ST-segment elevation in the lead augmented vector right (aVR) in 12-lead electrocardiography may indicate the possibility of coronary artery disease involving the left main coronary artery or proximal left anterior descending artery, pulmonary embolism or takotsubo cardiomyopathy. We report a 69-year-old female with severe aortic stenosis, who had similar electrocardiographic findings which indicated ischemic change and led to cardiogenic shock and ventricular tachycardia. Intubation and insertion of an intra- aortic balloon pump (IABP) were performed and the result of coronary angiography showed only less than 40% stenosis. Her blood pressure gradually stabilized, and diffuse ST-segment depression or ST-segment elevation in lead aVR was not noted in the 12-lead electrocardiography. However, we removed the IABP and after 6 hours, sudden profound shock refractory to combined vasopressors occurred. Electrocardiography again showed ST- segment elevation in aVR with and diffuse ST-segment depression. After several episodes of ventricular tachycardia, cardiopulmonary resuscitation was not successful and the patient expired in our hospital. KEY WORDS: Diffuse ST depression; Severe aortic stenosis; ST elevation in aVR.

Prevalence of prehypertension and associated risk factors in a rural Taiwanese adult population.

BACKGROUND: The Joint National Committee on the Prevention, Detection, Evaluation, and Treatment of High Blood Pressure has recently introduced the prehypertension category of blood pressure status that needs monitoring and intervention. This study aimed to assess the prevalence of prehypertension and its associated risks in rural Taiwan. METHODS: From community-based cross-sectional data of 6204 adults (2650 men and 3554 women) who received general health examination in the Chi-Shan district in rural Taiwan, collected between 2002 and 2007, we analyzed and compared the blood pressure and demographic, metabolic, and behavior characteristics of prehypertensive and normotensive subjects. Multiple logistic regression methods were used to identify risk factors for prehypertension. RESULTS: Within the study population, 3354 had hypertension, 1875 had prehypertension, and 975 had normal blood pressure. The prehypertensive subjects were older, had higher body mass index (BMI), and had higher blood glucose, total cholesterol, triglycerides, and uric acid levels than did the normotensive group. Multivariate logistic regression analysis revealed that BMI was the strongest predictor of prehypertension in both men and women (OR=1.102, 95% CI=1.054-1.152, P<0.001; and OR=1.121, 95% CI=1.085-1.159, P<0.001, respectively). CONCLUSIONS: The prevalence of prehypertension is high among adults in rural Taiwan and it was associated with many risk factors for further hypertension and cardiovascular disease. Early lifestyle modifications, such as healthy diet, optimal weight control, and exercise are recommended interventions.

Traumatic tricuspid insufficiency with chordae tendinae rupture: a case report and literature review.

With the increase in the number of automobile accidents, traumatic tricuspid insufficiency, a rare complication of non-penetrating blunt chest injury, has become an important problem. This kind of injury has been found more frequently during the last decade, partly because of better diagnostic procedures and a better understanding of the pathology. Here, we report a 22-year-old male patient who suffered chest trauma from an automobile accident. Echocardiography demonstrated tricuspid chordae tendinae rupture with remarkable tricuspid regurgitation. We discuss this case in comparison with the previous literature. This case reminds us that physicians in the emergency department should be aware of this potential complication following non-penetrating chest trauma.

Validation of a new index for estimating arterial stiffness: measurement of the QPV interval by Doppler ultrasound.

BACKGROUND: Pulse wave velocity (PWV), a relevant indicator of arterial stiffness, can be measured noninvasively with a variety of automatic devices, but most are complexly equipped. We developed a novel index for estimating arterial stiffness as "QPV interval," which was determined by means of surface electrocardiogram and Doppler ultrasound of the brachial artery simultaneously. HYPOTHESIS: This study aimed to validate the QPV interval as an exact and convenient index for estimation of arterial stiffness. METHODS: Forty-seven patients with untreated essential hypertension and 19 normotensive subjects were enrolled. Brachial-ankle PWV (baPWV) was measured using an automatic volume-plethysmographic apparatus, and Doppler ultrasound was implemented sequentially to measure the QPV interval in each subject. Clinical biochemistry and echocardiography were performed on the same day. RESULTS: Mean baPWV was significantly higher in hypertensive patients than in normotensive subjects (p = 0.002), whereas mean QPV interval was significantly shorter in hypertensive patients than in the normotensive group (p = 0.019). A simple regression analysis demonstrated an inverse correlation between the QPV interval and baPWV (r = -0.671, p < 0.001) in all enrolled subjects. In a stepwise regression model that adjusted for age, systolic blood pressure, and other determinants of baPWV, the negative association remained between the QPV interval and baPWV (p < 0.001). CONCLUSION: The QPV interval correlates inversely with baPWV, independent of age and other determinants of baPWV; hence, the QPV interval can serve as a simple and convenient index for assessing arterial stiffness in clinical practice.