Silent myocardial ischaemia in treated hypertensives with and without left ventricular hypertrophy

[Characteristics of risk factors in young and middle-aged patients with first hemispheric ischemic stroke]

AIM

To compare risk factors of the first hemispheric ischemic stroke in young, middle and old age groups.

MATERIAL AND METHODS

One hundred and thirteen patients with first hemispheric ischemic stroke confirmed by CT/MRI were examined. The patients were divided into 2 groups: young and middle-aged (51 patients, 24 women, 27 men, mean age 49.8±5.2) and advanced-aged (62 patients, 30 women, 32 men, mean age 76.4±7.5). The frequency and duration of the following risk factors for ischemic stroke, including arterial hypertension, ischemic heart disease and arrhythmias, diabetes, smoking, family history of myocardial infarction and/or stroke, body mass index, acute emotional stress before the onset of the disease, were compared. Results of echocardiography, Holter and blood pressure monitoring, total cholesterol, low and high-density lipoproteins, triglycerides and blood glucose were analyzed.

RESULTS

In young and middle-aged patients, an increased variability of blood pressure, acute emotional stress before the onset of stroke, a family history of cardiovascular and/or cerebrovascular disease, a decreased level of high-density lipoproteins, silent myocardial ischemia on Holter monitoring, mitral and tricuspid valve prolapse, minor abnormalities of the heart were more frequent than in the advanced age group.

CONCLUSION

There are age-related differences in the spectrum and frequency of risk factors in patients with first hemispheric ischemic stroke. This fact should be taken into account in stroke prevention programs in various age groups.

Prognostic value of ST-T abnormalities and left high R waves with cardiovascular mortality in Japanese (24-year follow-up of NIPPON DATA80)

Little is known about the prognostic value of ST-segment depression and/or T wave (ST-T abnormalities) with or without left high R waves on electrocardiogram recorded at rest for death from cardiovascular disease (CVD) in Asian populations. Japanese participants without a history of CVD and free of major electrocardiographic (ECG) abnormalities were followed for 24 years. Subjects were divided into 4 groups based on baseline ECG findings: isolated left high R waves, isolated ST-T abnormalities, ST-T abnormalities with left high R waves, and normal electrocardiogram. Cox proportional hazard model was used to estimate risk of CVD mortality in groups with ECG abnormalities compared to the normal group. Of 8,572 participants (44.4% men, mean age 49.5 years; 55.6% women, mean age 49.4 years), 1,142 had isolated left high R waves, 292 had isolated ST-T abnormalities, and 128 had ST-T abnormalities with left high R waves at baseline. Multivariable-adjusted hazard ratios of ST-T abnormalities with left high R waves for CVD mortality were 1.95 (95% confidence interval 1.25 to 3.04) in men and 2.68 (95% confidence interval 1.81 to 3.97) in women. Isolated ST-T abnormalities increased the risk for CVD death by 1.66 times (95% confidence interval 1.01 to 2.71) in men and 1.62 times (95% confidence interval 1.18 to 2.24) in women. Association of ECG abnormalities with CVD mortality was independent of age, body mass index, systolic blood pressure, serum cholesterol, blood glucose, smoking and drinking, and antihypertensive medication. In conclusion, ST-T abnormalities with or without left high R waves on electrocardiogram recorded at rest constitute an independent predictor of CVD mortality in Japanese men and women.

Hypertension and myocardial ischemia

Detailed studies over the past 30 years have built up an impressive evidence base for the presence of myocardial ischemia in patients who have hypertension. This relationship ranges from the obvious association with obstructive coronary artery disease to mechanisms related to hemodynamic, microcirculatory, and neuroendocrine abnormalities. All of these factors serve to destabilize the critical balance between myocardial oxygen supply and demand. We have at our disposal a range of sophisticated investigations that allow us to demonstrate the presence and extent of the ischemia and therefore to target specific therapies to reduce the risk to these patients. Achieving target BP and managing all reversible components of the patient's cardiovascular risk status reduce to a minimum the clinical sequelae of myocardial ischemia in this vulnerable population..

Myocardial ischemia during everyday life in patients with arterial hypertension: prevalence, risk factors, triggering mechanism and circadian variability

INTRODUCTION

The objective of the present study was to investigate the prevalence, the risk factors, the hemodynamic triggering mechanisms, the circadian variability of ST segment depression (ST depression) and the effect of day and night fall in blood pressure on the prevalence of ST depression in hypertensive patients.

MATERIALS AND METHODS

In a multicentric study in Germany, 1,244 CardioTens registrations (combined 24-h ambulatory blood pressure measurement/electrocardiography with ST segment triggering; Meditech, Budapest, Hungary) from patients with arterial hypertension were consecutively monitored and evaluated centrally at the University of Bonn. Inclusion criterion was treated or untreated arterial hypertension. The ST segment was measured in accordance with the "1 : 1 : 1 rule" (horizontal or descending ST depression by 1 mm, 1 min duration, 1 min interval from the previous episode).

RESULTS

ST segment depression was observed in 250 (20.1%) patients; 90.3% of the transient ST-segment depression was silent (without angina pectoris). Ambulatory 24-h blood pressure measurement, but not office-based blood pressure measurement, was predictive for the occurrence of ST-segment depression. Risk factors for ST-segment depression were the Sokolow index > or =3.5 mV, smoking status, severity of coronary heart disease, use of diuretics, reduced left ventricular function, pulse pressure > or =60 mmHg and increase of double product (1,000 mmHg/min). A significant rise of the systolic/diastolic blood pressure (+8+ or -18/+7+ or -10 mmHg), of the heart rate (+12+ or -13/min) and of the double product (+2,471+ or -2,517 mmHg/min) was found during the transient ST depression as compared with the corresponding 24-h ambulatory blood pressure measurement mean values (P<0.0001 for all parameters specified). In most intermittent ST depressions, a rise of the double product was seen (n=789 episodes), and in the remaining 239 ST depressions, a fall of the double product was observed. ST depressions with fall of the double product showed a circadian distribution with a peak in the late evening. ST depression accompanied by a rise in double product showed two peaks (one in the early morning and one in the late evening). The prevalence of ST depression was significantly higher (28.6%) in extreme dippers than in dippers (18.2%), risers (21.8%) and non-dippers (19.6%).

CONCLUSIONS

ST depressions have a high prevalence of 20.1% in hypertensive patients. Clinical predictors for the occurrence of ST-segment depression were classical risk factors and cardiac target organ damage. Office-based blood pressure measurement was not a useful measuring tool for forecasting the likelihood of ST-segment depression. ST depressions were triggered inter alia by variations of blood pressure and the heart rate. The circadian variability of the ST depressions is crucially affected by the pressure double product characteristics on which the ST depression is based.

Electrocardiogram Screening for Left High R-Wave Predicts Cardiovascular Death in a Japanese Community-Based Population: NIPPON DATA90

Little is known about the efficacy of left ventricular hypertrophy diagnosed by electrocardiography for predicting cardiovascular disease in a general Japanese population. In a large cohort of participants selected randomly from the overall Japanese population, we attempted to evaluate the usefulness of a high amplitude R-wave (left high R-wave) on the electrocardiogram for predicting cardiovascular death. A total of 6,688 Japanese (mean age, 50.7 years old; 57% women) free of previous cardiovascular disease and use of antihypertensive agents at baseline were followed for 10 years, from 1990 to 2000. Left high R-wave on the electrocardiogram (the Minnesota Code, 3-1 or 3-3) was found in 9.4% of the 6,688 participants, in 14.6% of the 2,413 hypertensives and in 6.4% [corrected] of the 4,275 normotensives. During the follow-up period, 133 [corrected] participants died due to cardiovascular disease. After adjustment for systolic blood pressure and other risk factors, left high R-wave conferred an increased risk of cardiovascular death; the hazard ratio among all the participants was 1.88 (95% confidence interval, 1.22-2.89; p < 0.01), that among hypertensives was 1.97 (1.20-3.24; p = 0.01), and that among normotensives was 1.66 (0.69-3.98; p = 0.26). The population attributable risk percent of left high R-wave for cardiovascular death was 7.6% among all participants, 12.4% among hypertensives and 4.1% among normotensives. Left high R-wave on electrocardiogram, irrespective of the level of systolic blood pressure, was a predictive marker for cardiovascular death among community-dwelling Japanese.