Brugada Syndrome: The Role of Risk Stratification in Selecting Patients for Implantable Cardioverter-defibrillator Placement.

Brugada syndrome (BS) is an inherited cardiac ion channelopathy that is a rare, but treatable, cause of sudden cardiac death (SCD). There are many studies that explore the management of symptomatic BS, but few trials have been conducted regarding management of asymptomatic Brugada patients. Asymptomatic BS patients are shown to be at increased risk (0.5%-1.5%) for SCD compared to the general population and account for nearly 20% of deaths from SCD in patients with structurally normal hearts. Treatment for asymptomatic BS patients is often debated with the current guidelines allowing for management decisions to be made on a case-by-case basis. Therapies include either anti-arrhythmic medications, implantable cardioverter-defibrillator (ICD) placement, or no active treatment. This review intended to assess whether ICD placement benefits asymptomatic BS patients and what criteria may be useful in selecting patients for ICD placement. Results showed that ICD placement can reduce mortality in select asymptomatic patients. There were certain risk factors that increased the likelihood that an asymptomatic patient would experience SCD and thus benefit from an ICD. These factors include an electrocardiogram(ECG) demonstrating spontaneous type 1 Brugada Syndrome and inducibility of ventricular tachyarrhythmias during electrophysiological study. Other variables including gender, family history of SCD, and the presence of SCN5A mutation were not predictive of arrhythmic events. Moreover, many patients can suffer complications from ICDs that can affect the quality of life including inappropriate shocks, device malfunction, infection, mental health problems, and difficulties with replacements. Guidelines for quantifying the risk of SCD relative to the risks associated with ICD placement are still poorly defined. These complications and risk factors should be taken into consideration in the context of a patient-centered discussion regarding ICD placement in asymptomatic patients.

Are there consequences of labeling patients with prehypertension? An experimental study of effects on blood pressure and quality of life.

OBJECTIVE: The prehypertension classification was introduced to facilitate prevention efforts among patients at increased risk for hypertension. Although patients who have been told that they have hypertension report worse outcomes than unaware hypertensives, little is known about whether or not prehypertension labeling has negative effects. We evaluated the effects of labeling individuals with prehypertension on blood pressure and health-related quality of life three months later. METHODS: One hundred adults (aged 19 to 82 [mean=40.0] years; 54% women; 64% racial/ethnic minorities) with screening blood pressure in the prehypertensive range (120-139/80-89 mmHg) and no history of diagnosis or treatment of elevated blood pressure were randomly assigned to either a "Labeled" group in which they were informed of their prehypertension, or an "Unlabeled" group in which they were not informed. Subjects underwent office blood pressure measurement, 24-hour ambulatory blood pressure monitoring and completed self-report questionnaires at baseline and at three months. RESULTS: Multilevel mixed effects regression analyses indicated that changes in the white coat effect, office blood pressure, mean daytime ambulatory blood pressure, and physical and mental health did not differ significantly between the two groups. Adjusting for age, sex, race/ethnicity and body mass index did not affect the results. CONCLUSION: These findings suggest that labeling patients with prehypertension does not have negative effects on blood pressure or quality of life. Additional research is needed to develop approaches to communicating with patients about their blood pressure that will maximize the clinical and public health impact of the prehypertension classification.

Relation between leukocyte telomere length and incident coronary heart disease events (from the 1995 Canadian Nova Scotia Health Survey).

Leukocyte telomere length has been proposed as a biomarker of cellular aging and atherosclerosis. The aim of this study was to determine whether leukocyte telomere length is independently associated with incident coronary heart disease (CHD) in the general population. Telomere length was measured using a polymerase chain reaction method for participants enrolled in the 1995 Nova Scotia Health Survey (NSHS95; n = 1,917). The primary end point was the first occurrence of a fatal or nonfatal CHD event. During a mean follow-up period of 8.7 years, 164 fatal or nonfatal CHD events occurred. Compared with participants in the longest tertile of telomere length, those in the middle and shortest tertiles had increased incidence of CHD events (6.2, 11.2, and 12.2 per 1,000 person-years, respectively). After adjustment for demographics, traditional risk factors, and inflammatory markers including high-sensitivity C-reactive protein, interleukin-6, and soluble intercellular adhesion molecule-1, those in the middle tertile had significantly elevated risk for incident CHD (hazard ratio 1.63, 95% confidence interval 1.07 to 2.51, p = 0.02) compared with the longest tertile, whereas the risk for those in the shortest tertile was nonsignificantly elevated (hazard ratio 1.25, 95% confidence interval 0.82 to 1.90, p = 0.30). In conclusion, these findings do not support a linear association between leukocyte telomere length and incident CHD risk in the general population.