Lasse Oikarinen

Left Atrial Size and Risk of Major Cardiovascular Events During Antihypertensive Treatment: Losartan Intervention for Endpoint Reduction in Hypertension Trial

The influence of left atrial size on cardiovascular events during antihypertensive treatment has not been reported previously from a long-term, prospective, randomized hypertension treatment trial. We recorded left atrial diameter by annual echocardiography and cardiovascular events in 881 hypertensive patients (41% women) with electrocardiographic left ventricular hypertrophy aged 55 to 80 (mean: 66) years during a mean of 4.8 years of randomized losartan- or atenolol-based treatment in the Losartan Intervention for Endpoint Reduction in Hypertension Study. During follow-up, a total of 88 primary end points (combined cardiovascular death, myocardial infarction, or stroke) occurred. In Cox regression, baseline left atrial diameter/height predicted incidence of cardiovascular events (hazard ratio: 1.98 per cm/m [95% CI: 1.02 to 3.83 per cm/m]; P=0.042) adjusted for significant effects of Framingham risk score and history of atrial fibrillation. Greater left atrial diameter reduction during follow-up was associated with greater reduction in left ventricular hypertrophy, absence of new-onset atrial fibrillation or mitral regurgitation during follow-up, and losartan-based treatment (B=−0.13±0.03 cm/m; P<0.001) in multiple linear regression, adjusting for baseline left atrial diameter/height. However, in time-varying Cox regression analysis, left atrial diameter reduction was not independent of left ventricular hypertrophy regression in predicting cardiovascular events during follow-up. In conclusion, left atrial diameter/height predicts risk of cardiovascular events independent of other clinical risk factors in hypertensive patients with left ventricular hypertrophy and may be useful in pretreatment clinical assessment of cardiovascular risk in these patients.

The early repolarization pattern in the general population: clinical correlates and heritability

OBJECTIVES This study sought to describe the clinical correlates and heritability of the early repolarization pattern (ERP) in 2 large, population-based cohorts. BACKGROUND There is growing recognition that ERP is associated with adverse outcomes. METHODS Participants of the Framingham Heart Study (FHS) (N = 3,995) and the Health 2000 Survey (H2K) (N = 5,489) were included. ERP was defined as a J-point elevation ≥0.1 mV in ≥2 leads in either the inferior (II, III, aVF) or lateral (I, aVL, V(4-6)) territory or both. We tested the association between clinical characteristics and ERP, and estimated sibling recurrence risk. RESULTS ERP was present in 243 of 3,955 (6.1%) of FHS and 180 of 5,489 (3.3%) of H2K subjects. Male sex, younger age, lower systolic blood pressure, higher Sokolow-Lyon index, and lower Cornell voltage were independently associated with the presence of ERP. In the FHS sample, siblings of individuals with ERP had an ERP prevalence of 11.6% (recurrence risk ratio of 1.89). Siblings of individuals with ERP had an increased unadjusted odds of ERP (odds ratio: 2.22, 95% confidence interval: 1.01 to 4.85, p = 0.047). CONCLUSIONS ERP has strong association with clinical factors and has evidence for a heritable basis in the general population. Further assessment of the genetic determinants of ERP is warranted.

Expedited PublicationThe Early Repolarization Pattern in the General Population: Clinical Correlates and Heritability

OBJECTIVES This study sought to describe the clinical correlates and heritability of the early repolarization pattern (ERP) in 2 large, population-based cohorts. BACKGROUND There is growing recognition that ERP is associated with adverse outcomes. METHODS Participants of the Framingham Heart Study (FHS) (N = 3,995) and the Health 2000 Survey (H2K) (N = 5,489) were included. ERP was defined as a J-point elevation ≥0.1 mV in ≥2 leads in either the inferior (II, III, aVF) or lateral (I, aVL, V(4-6)) territory or both. We tested the association between clinical characteristics and ERP, and estimated sibling recurrence risk. RESULTS ERP was present in 243 of 3,955 (6.1%) of FHS and 180 of 5,489 (3.3%) of H2K subjects. Male sex, younger age, lower systolic blood pressure, higher Sokolow-Lyon index, and lower Cornell voltage were independently associated with the presence of ERP. In the FHS sample, siblings of individuals with ERP had an ERP prevalence of 11.6% (recurrence risk ratio of 1.89). Siblings of individuals with ERP had an increased unadjusted odds of ERP (odds ratio: 2.22, 95% confidence interval: 1.01 to 4.85, p = 0.047). CONCLUSIONS ERP has strong association with clinical factors and has evidence for a heritable basis in the general population. Further assessment of the genetic determinants of ERP is warranted.

QRS Duration and QT Interval Predict Mortality in Hypertensive Patients With Left Ventricular Hypertrophy: The Losartan Intervention for Endpoint Reduction in Hypertension Study

Abstract—Left ventricular hypertrophy is a risk factor for cardiovascular mortality, including sudden cardiac death. Experimentally, left ventricular hypertrophy delays ventricular conduction and prolongs action potential duration. Electrocardiographic QRS duration and QT interval measures reflect these changes, but whether these measures can further stratify risk in patients with electrocardiographic left ventricular hypertrophy is unknown. We measured the QRS duration and QT intervals from the baseline 12-lead electrocardiograms in the Losartan Intervention For Endpoint Reduction in Hypertension (LIFE) study, which included hypertensive patients with electrocardiographic evidence of left ventricular hypertrophy randomized to either losartan-based or atenolol-based treatment to lower blood pressure. In the present study, we related study baseline electrocardiographic measures to cardiovascular and all-cause mortality. There were 5429 patients (male 45.8%; mean age 66±7 years) included in the present analyses. After a mean follow-up of 4.9±0.8 years, there were 417 deaths from all causes, including 214 cardiovascular deaths. In separate univariate Cox regression analyses, QRS duration and several QT measures were significant predictors of cardiovascular mortality and all-cause mortality. However, in multivariate Cox analyses including all electrocardiographic measures and adjusting for other risk factors as well as treatment strategy, only QRS duration and maximum rate-adjusted QTapex interval remained as significant independent predictors of cardiovascular (P =0.022 and P =0.037, respectively) and all-cause mortality (P =0.038 and P =0.002, respectively). In conclusion, in a hypertensive risk population identified by electrocardiographic left ventricular hypertrophy, increased QRS duration and maximum QTapex interval can further stratify mortality risk even in the setting of effective blood pressure-lowering treatment.

Electrocardiographic Strain Pattern and Prediction of Cardiovascular Morbidity and Mortality in Hypertensive Patients

The ECG strain pattern of lateral ST depression and T-wave inversion is a marker for left ventricular hypertrophy (LVH) and adverse prognosis in population studies. However, whether ECG strain is an independent predictor of cardiovascular (CV) morbidity and mortality in the setting of aggressive antihypertensive therapy is unclear. ECGs were examined at study baseline in 8854 hypertensive patients with ECG LVH who were treated in a blinded manner with atenolol- or losartan-based regimens. Strain was defined by the presence of a downsloping convex ST segment with an inverted asymmetrical T wave opposite to the QRS axis in leads V5 and/or V6 and was present in 971 patients (11.0%). The Losartan Intervention For Endpoint reduction in hypertension (LIFE) study composite end point of CV death or nonfatal myocardial infarction or stroke occurred in 1035 patients (11.7%). In Cox analyses adjusting only for treatment effect, ECG strain was a significant predictor of CV death (hazard ratio [HR] 2.26, 95% confidence interval [CI] 1.78 to 2.86), fatal/nonfatal myocardial infarction (HR 2.16, 95% CI 1.67 to 2.80), fatal/nonfatal stroke (HR 1.76, 95% CI 1.39 to 2.21), and the composite CV end point (HR 1.99, 95% CI 1.70 to 2.33). After further adjusting for standard CV risk factors, baseline blood pressure, and severity of ECG LVH, ECG strain remained a significant predictor of CV mortality (HR 1.53, 95% CI 1.18 to 2.00), myocardial infarction (HR 1.55, 95% CI 1.16 to 2.06), and the composite CV end point (HR 1.33, 95% CI 1.11 to 1.59). Thus, ECG strain is a marker of increased CV risk in hypertensive patients in the setting of aggressive blood pressure lowering, independent of baseline severity of ECG LVH.

Relationship of the electrocardiographic strain pattern to left ventricular structure and function in hypertensive patients: the LIFE study☆

OBJECTIVES This study was designed to assess the relation of electrocardiographic (ECG) strain to increased left ventricular (LV) mass, independent of its relation to coronary heart disease (CHD). BACKGROUND The classic ECG strain pattern, ST depression and T-wave inversion, is a marker for left ventricular hypertrophy (LVH) and adverse prognosis. However, the independence of the relation of strain to increased LV mass from its relation to CHD has not been extensively examined. METHODS Electrocardiograms and echocardiograms were examined at study baseline in 886 hypertensive patients with ECG LVH by Cornell voltage-duration product and/or Sokolow-Lyon voltage enrolled in the Losartan Intervention For End point (LIFE) echocardiographic substudy. Strain was defined as a downsloping convex ST segment with inverted asymmetrical T-wave opposite to the QRS axis in leads V5 and/or V6. RESULTS Strain occurred in 15% of patients, more commonly in patients with than without evident CHD (29%, 51/175 vs. 11%, 81/711, p < 0.001). When differences in gender, race, diabetes, systolic pressure, serum creatinine and high density lipoprotein cholesterol were controlled, strain on baseline ECG was associated with greater indexed LV mass in patients with (152 +/- 33 vs. 131 +/- 32 g/m2, p < 0.001) or without CHD (131 +/- 24 vs. 119 +/- 22 g/m2, p < 0.001). In logistic regression analyses, strain was associated with an increased risk of anatomic LVH in patients with CHD (relative risk 5.14, 95% confidence interval [CI] 1.16 to 22.85, p = 0.0315), without evident CHD (relative risk 2.91, 95% CI 1.50 to 5.65, p = 0.0016), and in the overall population when CHD was taken into account (relative risk 2.98, 95% CI 1.65 to 5.38, p = 0.0003). CONCLUSIONS When clinical evidence of CHD is accounted for, ECG strain is likely to indicate the presence of anatomic LVH. Greater LV mass and higher prevalence of LVH in patients with strain offer insights into the known association of the strain pattern with adverse outcomes.

Relation of QT interval and QT dispersion to echocardiographic left ventricular hypertrophy and geometric pattern in hypertensive patients. The LIFE study.

Objective In hypertensive patients, left ventricular hypertrophy (LVH) predicts increased mortality, in part due to an increased incidence of sudden death. Repolarization-related arrhythmogenesis may be an important mechanism of sudden death in hypertensive patients with LVH. Increased QT interval and QT dispersion are electrocardiographic (ECG) measures of ventricular repolarization, and also risk markers for ventricular tachyarrhythmias. We assessed the relation of QT intervals and QT dispersion to echocardiographically determined left ventricular (LV) mass and geometry in a large population of hypertensive patients with ECG evidence of LVH. Methods QT intervals and QT dispersion were determined from baseline 12-lead ECGs in 577 (57% male; mean age 65 ± 7 years) participants in the LIFE study. LV mass index (LVMI) and geometric pattern were determined by echocardiography and QT interval duration and QT dispersion were assessed in relation to gender-specific LVMI quartiles. Results In both genders, increasing LVMI was associated with longer rate-adjusted QT intervals. QT dispersion measures showed a weaker association with LVMI quartiles. Both concentric and eccentric LVH were associated with increased QT interval duration and QT dispersion. These relations remained significant after controlling for relevant clinical variables. Conclusions In hypertensive patients with ECG evidence of LVH, increased LVMI and LVH are associated with a prolonged QT interval and increased QT dispersion. These findings suggest that an increased vulnerability to repolarization-related ventricular arrhythmias might in part explain the increased risk of sudden death in hypertensive patients with increased LV mass.

Electrocardiographic Strain Pattern and Prediction of New-Onset Congestive Heart Failure in Hypertensive Patients The Losartan Intervention for Endpoint Reduction in Hypertension (LIFE) Study

Background— The ECG strain pattern of ST depression and T-wave inversion is strongly associated with left ventricular hypertrophy (LVH) independently of coronary heart disease and with an increased risk of cardiovascular morbidity and mortality in hypertensive patients. However, whether ECG strain is an independent predictor of new-onset congestive heart failure (CHF) in the setting of aggressive antihypertensive therapy in unclear. Methods and Results— The relationship of ECG strain at study baseline to the development of CHF was examined in 8696 patients with no history of CHF who were enrolled in the Losartan Intervention for Endpoint Reduction in Hypertension (LIFE) study. All patients had ECG LVH by Cornell product and/or Sokolow-Lyon voltage criteria on a screening ECG, were treated in a blinded manner with atenolol- or losartan-based regimens, and were followed up for a mean of 4.7±1.1 years. Strain was defined as a downsloping convex ST segment with inverted asymmetrical T-wave opposite the QRS axis in lead V5 or V6. ECG strain was present in 923 patients (10.6%), and new-onset CHF occurred in 265 patients (3.0%), 26 of whom had a CHF-related death. Compared with patients who did not develop CHF, hypertensive patients who developed CHF were older; were more likely to be black, current smokers, and diabetic; were more like to have a history of myocardial infarction, ischemic heart disease, stroke, or peripheral vascular disease; and had greater baseline severity of LVH by Cornell product and Sokolow-Lyon voltage, higher baseline body mass indexes, higher serum glucose levels and albuminuria, similar baseline systolic and diastolic pressures, and reductions in diastolic pressure with treatment but greater reductions in systolic pressure. In univariate Cox analyses, ECG strain was a significant predictor of new-onset CHF (hazard ratio [HR], 3.27; 95% CI, 2.49 to 4.29) and CHF mortality (HR, 4.74; 95% CI, 2.11 to 10.64). In Cox multivariable analyses adjusting for baseline differences between patients with and without new-onset CHF, in-treatment differences in systolic and diastolic pressures, Sokolow-Lyon voltage, and Cornell product, and the impact of treatment with losartan versus atenolol on outcomes, ECG strain remained a significant predictor of incident CHF (HR, 1.80; 95% CI, 1.30 to 2.48) and CHF-related death (HR, 2.78; 95% CI, 1.02 to 7.63). Conclusions— ECG strain identifies hypertensive patients at increased risk of developing CHF and dying as a result of CHF, even in the setting of aggressive blood pressure lowering.

Reductions in albuminuria and in electrocardiographic left ventricular hypertrophy independently improve prognosis in hypertension : the LIFE study.

Background In the Losartan Intervention For Endpoint reduction in hypertension (LIFE) study, reduced urine albumin/creatinine ratio (UACR) as well as regression of left ventricular hypertrophy have been associated with lower incidence of cardiovascular events. We wanted to investigate whether these prognostic improvements were independent. Methods In 6679 hypertensive patients included in the LIFE study, we measured UACR, left ventricular hypertrophy by electrocardiography, serum cholesterol, plasma glucose and blood pressure after 2 weeks of placebo treatment and again after 1 year of anti-hypertensive treatment with either an atenolol- or a losartan-based regimen. During this first year of treatment, 77 patients encountered a non-fatal stroke or myocardial infarction and were excluded to avoid bias. During the next 3–4 years, 610 composite endpoints [cardiovascular death (n = 228), fatal or non-fatal myocardial infarction or stroke] were recorded. Results In Cox regression analyses, the composite endpoint was after adjustment for treatment allocation predicted by baseline logUACR [hazard ratio (HR) = 1.16 per 10-fold increase, P < 0.05], 1-year logUACR (HR = 1.29 per 10-fold increase), baseline Sokolow–Lyon voltage (HR = 1.01 per mm, both P < 0.001) and 1-year Cornell product (HR = 1.01 per 100 mm × ms, P < 0.01). Cardiovascular death was predicted by 1-year logUACR (HR = 1.59, P < 0.001), baseline Sokolow–Lyon voltage (HR = 1.01, P = 0.06) and 1-year Cornell product (HR = 1.02, P < 0.001). Both were predicted independent of age, Framingham risk score, current smoking, history of cardiovascular disease and diabetes. Gender, serum cholesterol, plasma glucose and blood pressure did not enter the models. Conclusions Baseline UACR and Sokolow–Lyon voltage, as well as in-treatment UACR and Cornell product, added to the risk prediction independent of traditional risk factors, indicating that albuminuria and left ventricular hypertrophy reflect different aspects of cardiovascular damage and are modifiable cardiovascular risk factors.

Ambulatory Electrocardiographic Evidence of Transmural Dispersion of Repolarization in Patients With Long-QT Syndrome Type 1 and 2

Background—Transmural dispersion of repolarization (TDR) may be related to the genesis of torsade de pointes (TdP) in patients with the long-QT (LQT) syndrome. Experimentally, LQT2 models show increased TDR compared with LQT1, and &bgr;-adrenergic stimulation increases TDR in both models. Clinically, LQT1 patients experience symptoms at elevated heart rates, but LQT2 patients do so at lower rates. The interval from T-wave peak to T-wave end (TPE interval) is the clinical counterpart of TDR. We explored the relationship of TPE interval to heart rate and to the presence of symptoms in patients with LQT1 and LQT2. Methods and Results—We reviewed Holter recordings from 90 genotyped subjects, 31 with LQT1, 28 with LQT2, and 31 from unaffected family members, to record TPE intervals by use of an automated computerized program. The median TPE interval was greater in LQT2 (112±5 ms) than LQT1 (91±2 ms) or unaffected (86±3 ms) patients (P <0.001 for all group comparisons), and the maximal TPE values differed as well. LQT1 patients showed abrupt increases in TPE values at RR intervals from 600 to 900 ms, but LQT2 patients did so at RR intervals from 600 to 1400 ms (longest RR studied). Asymptomatic and symptomatic patients showed similar TDRs. Conclusions—TDR is greater in LQT2 than in LQT1 patients. LQT1 patients showed a capacity to increase TDR at elevated heart rates, but LQT2 patients did so at a much wider rate range. The magnitude of TDR is not related to a history of TdP.