Ethnic differences in lifetime cumulative incidence of syncope: the Malaysian elders longitudinal research (MELoR) study.

PURPOSE: To determine the lifetime cumulative incidence of syncope, potential ethnic differences and factors associated with syncope using the Malaysian elders longitudinal research (MELoR) study first wave dataset. METHODS: The MELoR study recruited community-dwelling adults aged 55 years and over, selected through stratified random sampling from three parliamentary constituencies. The baseline data collected during the first wave was obtained through face-to-face interviews in participants' homes using computer-assisted questionnaires. During their baseline assessments, participants were asked whether they had ever experienced a blackout in their lifetime and if they had experienced a blackout in the preceding 12 months. RESULTS: Information on blackouts and ethnicity were available for 1530 participants. The weight-adjusted lifetime cumulative incidence of syncope for the overall population aged 55 years and above was 27.7%. The estimated lifetime cumulative incidence according to ethnic groups was 34.6% for Malays, 27.8% for Indians and 23.7% for Chinese. The estimated 12-month incidence of syncope was 6.1% overall, equating to 11.7% for Malays, 8.7 % for Indians and 2.3% for Chinese. Both Malay [odds ratio (OR) 1.46; 95% confidence interval (CI) 1.10-1.95 and OR 3.62, 95% CI 1.96-6.68] and Indian (OR 1.34; 95% CI 1.01-1.80 and OR 3.31, 1.78-6.15) ethnicities were independently associated with lifetime and 12-month cumulative incidence of syncope, respectively, together with falls, dizziness and myocardial infarction. CONCLUSION: Ethnic differences exist for lifetime cumulative incidence of syncope in community-dwelling individuals aged 55 years and over in an urban area in Southeast Asia. Future studies should now seek to determine potential genetic, cultural and lifestyle differences which may predispose to syncope.

Mass fainting in garment factories in Cambodia.

This paper reports an ethnographic study of mass fainting among garment factory workers in Cambodia. Research was undertaken in 2010-2015 in 48 factories in Phnom Penh and 8 provinces. Data were collected in Khmer using nonprobability sampling. In participant observation with monks, factory managers, health workers, and affected women, cultural understandings were explored. One or more episodes of mass fainting occurred at 34 factories, of which 9 were triggered by spirit possession. Informants viewed the causes in the domains of ill-health/toxins and supernatural activities. These included "haunting" ghosts at factory sites in the wake of Khmer Rouge atrocities or recent fatal accidents and retaliating guardian spirits at sites violated by foreign owners. Prefigurative dreams, industrial accidents, or possession of a coworker heralded the episodes. Workers witnessing a coworker fainting felt afraid and fainted. When taken to clinics, some showed signs of continued spirit influence. Afterwards, monks performed ritual ceremonies to appease spirits, extinguish bonds with ghosts, and prevent recurrence. Decoded through its cultural motifs of fear and protest, contagion, forebodings, the bloody Khmer Rouge legacy, and trespass, mass fainting in Cambodia becomes less enigmatic.

Implications of a History of Syncope in Patients Hospitalized With Heart Failure.

We assessed the frequency and implications of a history of syncope of up to 1 year prior to hospitalization with acute heart failure (AHF) between February and November 2012. Data were collected for 5005 patients hospitalized with AHF and analyzed and compared according to the absence/presence of a history of syncope (group 1 vs group 2). Prior syncope among patients with heart failure was 5.3%. Age, gender, hypertension, atrial fibrillation, bundle branch block, left ventricular ejection fraction (LVEF), and obstructed coronary vessels were comparable in the 2 groups. Group 2 patients were more likely to smoke or have diabetes mellitus, stroke, and cardiac arrest. Group 2 patients frequently required aggressive treatment and had more worse in-hospital and 1-year outcomes compared to group 1. After adjustment for age, sex, ethnicity, and LVEF, multivariate regression analysis showed that history of syncope predicted in-hospital mortality (odds ratio: 2.61; 95% confidence interval: 1.707-4.002). History of syncope during the year prior to the index admission with AHF is a marker of worse outcomes regardless of patient age and LVEF. Further studies are required to confirm this observation and its clinical implications.

Prevalence and significance of early repolarisation in a black African population: data of 246 individuals with cardiovascular morbidity.

BACKGROUND: Early repolarisation (ER) is commonly seen on electrocardiograms (ECG). Recent reports have described the relationship between ER and sudden cardiac death (SCD). The prevalence and significance of ER have not been studied in black Africans. METHOD: We matched clinical and ECG records of subjects over 18 years of age who consulted a cardiac unit in two medical centres of Douala, Cameroon. A questionnaire focusing on past history of syncope or family history of sudden unexplained death (SUD) was filled in by each subject. A 12-lead ECG was recorded by a trained nurse and analysed by two independent physicians. RESULTS: Of the 752 ECGs recorded, we studied 246 index cases. The mean age of subjects was 45 ± 16 years and 53% were female. Almost 57% had hypertension, 41% had palpitations and 18% reported a history of syncope. ER pattern was found in 20% [slurring in three (3%), notching in 13% and both in three (7%)]. ER subjects were younger than those without (41 ± 16 vs 49 ± 16 years, p = 0.0048). Lead localisation was predominantly the laterals for the slurring pattern, whereas the inferior and lateral leads were equally involved for the notching pattern. Negative T waves in the infero-lateral leads were associated with ER (p = 0.00025). Among the subjects with syncope, 41% displayed ER and 13% did not have ER (p = 0.00014). The notching pattern seemed to be associated with syncope (p = 0.00011). CONCLUSION: Early repolarisation is frequent in black Africans, especially in the setting of cardiovascular morbidity. Early repolarisation may be associated with a past history of syncope, especially the notched pattern.

Validation of the San Francisco Syncope Rule in two hospital emergency departments in an Asian population.

OBJECTIVES: The objective was to externally validate the ability of the San Francisco Syncope Rule (SFSR) to accurately identify patients who will experience a 7-day serious clinical event in an Asian population. METHODS: This was a prospective cohort study, with a sample of adult patients with syncope and near-syncope enrolled. Patients 12 years old and below and patients with loss of consciousness after head trauma, a witnessed seizure, with known alcohol or illicit drug ingestion, and altered level of consciousness or persistent new neurologic deficits were excluded. The patients were evaluated for the presence of one or more of the five SFSR variables: shortness of breath, history of heart failure, hematocrit <30%, systolic blood pressure <90 mm Hg, and abnormal electrocardiogram (ECG). The patients were followed up by medical record review or telephone interview. Seven-day outcomes were death, arrhythmia, myocardial infarction, acute pulmonary edema, significant structural heart disease, pulmonary embolism, major cardiac procedure, stroke, subarachnoid hemorrhage, major bleeding, and anemia. RESULTS: A total of 1,250 patients from two centers were recruited. Fifty-six patients were excluded from primary analysis because of incomplete data (n = 55) and/or they were noncontactable for follow-up (n = 32). Of the 1,194 patients analyzed, 138 patients (11.6%) experienced adverse outcomes at 7 days. The rule performed with a sensitivity of 94.2% (95% confidence interval [CI] = 89.0% to 97.0%) and a specificity of 50.8% (95% CI = 47.7% to 53.8%). CONCLUSIONS: In this study, SFSR rule had a sensitivity of 94.2%. This suggests caution on the strict application of the rule to all patients presenting with syncope. It should only be used as an aide in clinical decision-making in this population.

Characteristics of syncope in Japan and the Pacific rim.

As is true in the Western world, syncope of cardiac and non-cardiac origin is one of the common clinical presentations in daily medical practice in Japan and Asia. However, the underlying disorders and social backgrounds associated with syncope may differ, from those encountered in Western countries, particularly in Japan. While non-cardiac causes, neurally-mediated reflex faints in particular, are highly prevalent, out-of-hospital deaths by drowning due to syncope occurring during bathing at home are not rare in Japan, particularly in the elderly. Other underlying cardiac or non-cardiac disorders are also noteworthy, particularly Brugada syndrome and coronary vasospasm, which may present as isolated syncope. In addition, the characteristic clinical presentation of micturition and defecation syncope is not uncommon. This review is focused on these specific underlying diseases in the light of the guidelines issued by the Japanese Circulation Society regarding the diagnosis and treatment of syncope.

Frequency of cardiac events at four years among initially asymptomatic filipinos with the Brugada type 1 electrocardiographic pattern.

Brugada type 1 electrocardiographic (ECG) pattern occurs in 0.2% of Filipinos. A knowledge gap exists on the natural course of asymptomatic patients with Brugada type 1 ECG pattern. Most studies that reported cohort event rates were taken from hospitals or referral centers. This is the first cohort from an entire country where the subjects were selected randomly. The objective of this study was to describe the frequency of cardiac events at 4 and 6 years of 7 patients with Brugada type 1 ECG pattern of 3,907 patients previously screened from the general population of the Philippines during the National Nutrition and Health Survey. Personal interviews at year 4 using a structured questionnaire were conducted by 1 of the investigators. Occurrences of major (syncope, seizure, unexplained accidents, sudden death) and minor events in subjects and their first- and second-degree relatives were elicited. Six-year follow-up by text messaging was conducted to ascertain vital status and occurrence of cardiac events. All 7 patients with Brugada type 1 ECG pattern were men. Three of the 7 initially asymptomatic subjects (43%, 95 confidence interval 6 to 80) developed a major cardiac event by the fourth year. Those with events were younger than those without events. All 7 were alive by the sixth year. No additional events were noted between the fourth and sixth years. In conclusion, cardiac events are considerable in initially asymptomatic Filipinos with Brugada type 1 ECG pattern.

Greater orthostatic tolerance in young black compared with white women.

We hypothesized that orthostatic tolerance is higher in young, healthy black compared with white women. To determine orthostatic tolerance, 22 women (11 black and 11 white) underwent graded lower body negative pressure to presyncope. We measured blood pressure, heart rate, and R-R interval (ECG) continuously at baseline and through all of the levels of lower body negative pressure. Blood samples were taken at baseline along with presyncope for the measurement of plasma catecholamine concentrations, serum aldosterone concentration, and plasma renin activity. Cumulative stress index, the sum of the product of time and lower body negative pressure, was the indicator of orthostatic tolerance. Orthostatic tolerance in the black women was greater than in the white women [cumulative stress index: -1003 (375) versus -476 (197); P<0.05]. Although plasma concentrations of norepinephrine increased in both groups at presyncope, the increase was greater in black [Deltaplasma concentrations of norepinephrine: 167 (123)] versus white women [86 (64); P<0.05], as was the increase in PRA [DeltaPRA 2.6 (1.0) versus 0.6 (0.9) ng of angiotensin II x mL(-1) x h(-1); P<0.05, for black and white women, respectively). Although heart rate increased and R-R interval decreased to a greater extent during lower body negative pressure in black women compared with white women (ANOVA: P<0.05), baroreflex function (ie, slope R-R interval versus systolic blood pressure) was unaffected by race. These data indicate that orthostatic tolerance is greater in black compared with white women, which appears to be a function of greater sympathetic nervous system responses to orthostatic challenges.

Early repolarization electrocardiography pattern with unexplained syncope during training in a young black African non-elite athlete: an accidental finding?

Until recently it was generally thought that early repolarization is benign. But a recent article in the NEJM (Haissaguerre et al.) suggests that some persons with early repolarization may be at risk of life-threatening ventricular tachyarrhythmia. Unexplained syncope or sudden death occurs mostly during sleep. However, some cases of cardiac arrest during exertion have been reported. We report the case of a 39 year-old black African male with early repolarization pattern on electrocardiogram who regularly experienced dizziness (and one episode of transient loss of consciousness) exclusively while exercising. Detailed examination was normal. Under quinidine therapy, he experienced no further episodes. Increasingly reported cases of cardiac arrest in Africans, and significant prevalence of early repolarization in this population, have to be taken into account since the Haissaguerre et al. report. Further evidence of the lethal consequences of this syndrome are needed, bearing in mind that diagnostic tools for life-threatening arrhythmias are often scarce in sub-Saharan Africa.

The Brugada syndrome in a Chinese population.

Sudden cardiac death has been reported in patients with a unique electrocardiographic (ECG) abnormality showing right bundle branch block and ST segment elevation in the precordial leads. This syndrome was first described by Brugada and Brugada and has not been previously described in a Chinese population. We report here the first three cases in Singapore. The first patient was a 49-year-old man who presented with syncope, associated with generalized convulsions. The second patient was a 25-year-old man who complained of palpitations but no syncope. The third patient was a 77-year-old man who presented with recurrent episodes of syncope and collapsed with ventricular fibrillation. All patients had no past cardiac or drug history of note. The neurological examination and investigations were normal. All three patients showed a unique right bundle branch block pattern with ST segment elevation in leads V1-3. The echocardiogram and 24-h ambulatory ECG monitoring, were normal. Single vessel disease was present in the third patient. Electrophysiological studies performed in all three patients were able to induce ventricular fibrillation. The patient with resuscitated cardiac death underwent an implantable cardioverter defibrillator implantation. The importance of this syndrome is that the recognition of the unique ECG pattern enables early identification and treatment of these patients.