Left atrial systolic force in hypertensive patients with left ventricular hypertrophy predicts atrial fibrillation

Background

Recently increased left atrial systolic force (LASF), a measure of left atrial function, has been associated with left ventricular hypertrophy (LVH) in hypertensive patients. Impaired left ventricular relaxation is often seen in hypertensive patients and because of the correlated left ventricular filling impairment the atrial contribution to ventricular filling is important. LASF may increase as a compensatory response to preserve a sufficient stroke volume, which partly could explain the association between age-related prolonged left ventricular relaxation and increased LASF. Reduced left atrial function has also been shown to be associated with poor prognosis in patients with atrial fibrillation. It remains unknown whether LASF can be used as a predictor of new-onset atrial fibrillation (NOAF). Furthermore, the influence of treatment with atenolol and losartan on LASF is unclear.

Purpose

We aimed to determine whether LASF correlates to incident atrial fibrillation and whether the preservation of LASF reduces the risk of new onset atrial fibrillation (NOAF).

Methods

N=758 patients without atrial fibrillation at baseline were enrolled from the Losartan Intervention For Endpoint reduction in hypertension (LIFE) echocardiography sub study. Participants of the LIFE-study were randomized to either atenolol- or losartan-based treatment. Mean follow-up was 59 month. LASF was calculated using average mitral orifice area and mitral peak A velocity obtained by Doppler echocardiography.

Results

At baseline 25% of patients had a LASF≤10.3kdyn. Compared to other quartiles this quartile had a higher proportion of men, lower heart rate, body mass index and age. After controlling for these variables patients in the first quartile had lower stroke volume compared to other quartiles. New-onset AF occurred in 29 (8.1/1,000 patients-years of follow-up) patients. In multivariable Cox regression analyses with backwards elimination increasing LASF was associated with lower risk of NOAF (HR=0.90 [95% confidence interval 0.85–0.96], p=0.001). Integrated discrimination improvement was 0.054 (p=0.004) and there was a borderline significant net reclassification improvement of 19.2% (p=0.075). Over time LASF decreased more in the atenolol-based than the losartan-based treatment group (p<0.001).

Conclusions

Low left atrial systolic force (LASF) was associated with higher risk of NOAF. Losartan-based treatment was associated with better preservation of LASF compared to atenolol-based treatment. Our data thus suggest that hypertensive patients with LVH and low LASF identifies a patient group with progressed left atrial dysfunction and with high risk of NOAF. Because of the preserving effect of losartan on the function and structure of the left atrium, treating hypertensive patients with LVH with losartan might decrease their risk of incident atrial fibrillation.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): The LIFE study originally received support from Merck & Co., Inc.

Incident atrial fibrillation and heart failure in treated hypertensive patients with left ventricular hypertrophy

Background

Hypertension and left ventricular hypertrophy (LVH) are predictors of atrial fibrillation (AF) and heart failure (HF). The incidence rates of AF and HF and especially the combination of these two complications in hypertensive patients with LVH receiving antihypertensive treatment are unknown, and so are the association with risk levels of other cardiovascular diseases and death in hypertensive patients with LVH who develop new onset AF and HF.

Purpose

We aimed to investigate the appearance and severity of AF and HF in 8,702 hypertensive patients aged 55–80 years with LVH receiving antihypertensive treatment in a prospective and randomized clinical trial primarily designed to investigate the preventive effect on a composite endpoint of myocardial infarction, stroke and cardiovascular death.

Methods

Included were patients who had sinus rhythm in ECG and no history of AF or HF when they were randomly allocated to blinded study medication with losartan or atenolol. Additional medication was given with hydrochlorothiazide and calcium antagonist if needed to gain blood pressure control. Incident AF was detected by annual ECGs and from adverse event reports submitted by the 930 clinical investigators. Incident HF was diagnosed according to Framingham criteria. Endpoints including incident HF, myocardial infarction, stroke and cardiovascular death were reported with relevant documentation by the investigators, and adjudicated by an expert endpoint committee.

Results

Incident AF occurred in 679 patients (7.8%) and HF in 246 patients (2.8%) during 4.7±1.1 years mean follow-up. Incident AF was associated with a >4-fold increased risk of developing subsequent HF (HR=4.7; 95% CIs, 3.1–7.0; P<0.001) in multivariable Cox analyses adjusting for age, sex, race, randomized treatment, standard cardiovascular risk factors and incident myocardial infarction. The development of HF as a time-dependent variable was associated with a multivariable-adjusted 3-fold increase of the primary study endpoint (HR=3.11; 95% CIs, 1.52 to 6.39; P<0.001) which was the composite of myocardial infarction, stroke or cardiovascular death.

Incident HF was associated with a >3-fold increased risk of developing subsequent AF (HR=3.3; 95% CIs, 2.3–4.9; P<0.001). This development of AF was associated with more than a 2-fold increase of the composite of myocardial infarction, stroke or cardiovascular death in multivariable Cox analysis (HR=2.26; 95% CIs, 1.09–4.67; P=0.028).

Conclusions

Incident atrial fibrillation and heart failure are associated with increased risk of the other in treated hypertensive patients with left ventricular hypertrophy. These hypertensive patients who subsequently develop both atrial fibrillation and heart failure during antihypertensive treatment have particularly high risk of an additional composite endpoint consisting of myocardial infarction, stroke or cardiovascular death.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): The study originally received support from Merck & Co., Inc.

High-sensitive Troponin T is not associated with the progression of asymptomatic mild to moderate aortic stenosis: a post hoc substudy of the SEAS trial

Background

Aortic stenosis (AS) and coronary artery disease (CAD) share pathophysiological pathways, as reflected by frequent concomitant revascularization in patients undergoing aortic valve replacement (AVR). High-sensitive Troponin T (hsTnT) is a proven biomarker of cardiomyocyte overload and injury, and predicts postoperative mortality after AVR. However, it is unknown if hsTnT can predict AVR, mortality or ischemic coronary events (ICE) in asymptomatic AS patients.

Purpose

To investigate the hypothesis that increased hsTnT is associated with more severe AS and a higher risk of adverse outcomes in asymptomatic AS patients without overt CAD.

Methods

hsTnT concentrations were examined at baseline and after 1-year follow-up in 1739 asymptomatic AS patients enrolled in the randomized, double-blind Simvastatin and Ezetimibe in Aortic Stenosis (SEAS) study. The main inclusion criteria were: left ventricular (LV) ejection fraction >55%, transaortic maximal velocity between 2.5–4.0 m/s, and no history of CAD. The primary exposure variable was increased hsTnT (>14 pg/mL according to the assay manufacturer, Roche). This study's primary endpoint was a composite of competing risk outcomes: all-cause mortality as the first event, AVR without revascularization, and ICE (defined as myocardial infarction before AVR, PCI before or combined with AVR, or any CABG). Multivariable regression examined associations between hsTnT and clinical variables. Cox proportional hazards regression models were adjusted for age, sex, creatinine, LV mass index, mean aortic pressure gradient (Pmean) and stratified by center and lipid-lowering treatment. We analyzed outcomes during 5-year follow-up from baseline.

Results

At baseline, 453 (26.0%) patients had increased hsTnT and 302 (17.4%) had moderate-severe AS with a mean (SD) aortic valve area of 0.8 (0.2) cm2 and Pmean of 33.2 (8.8) mmHg. The median annual hsTnT change from baseline to year 1 was 0.8 pg/mL (IQR, −0.4 to 2.3), regardless of AS severity (P=0.08). In adjusted models, log(hsTnT at baseline) was associated with age, sex, creatinine, and LV mass index (all P<0.05), but not with AS severity (P=0.36). The incidence rate ratio for ICE (Figure 1) in patients with increased vs normal baseline hsTnT concentrations was 2.32 (95% CI, 1.72–3.11, P<0.001). In adjusted Cox regression, increased hsTnT was associated with an increased 5-year ICE risk (HR 1.64; 95% CI, 1.18–2.29, P=0.003), but neither with AVR without revascularization nor death (Figure 1).

Conclusion

In these asymptomatic AS patients without overt CAD, hsTnT is often normal and remains stable during 1 year of follow-up regardless of AS severity. Increased hsTnT is associated with CAD-related events, but neither to AS severity nor AVR without concomitant revascularization. This analysis does not support routine hsTnT measurement in asymptomatic AS to predict AVR related to AS progression, although hsTnT could improve the risk assessment for ICE.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Main sponsor (SEAS): Merck & Co Inc, Whitehouse Station, New JerseyBlood analysis sponsor: Roche Diagnostics International Ltd, Switzerland

High-sensitive Troponin T in asymptomatic aortic stenosis

Background

High-sensitive cardiac Troponin T (hsTnT) is the most frequently used biomarker for the detection of cardiomyocyte injury. Severe aortic stenosis (AS) leads to an increased left ventricular load, with the potential of myocardial injury reflected by increased TnT levels. However, there is a lack of studies showing the prevalence and prognostic role of elevated hsTnT in patients with asymptomatic AS.

Purpose

To examine the association between the hsTnT levels and AS severity in asymptomatic AS patients. We hypothesized that patients with more severe AS will have elevated hsTnT levels and that hsTnT levels are associated with a higher risk for aortic valve events (AVE) and all-cause mortality (ACM).

Methods

We performed a post-hoc analysis in 1739 asymptomatic patients with mild to moderate-severe AS, enrolled in the randomized, double-blinded SEAS-study (Simvastatin and Ezetimibe in Aortic Stenosis). All patients had available hsTnT blood samples measured at baseline (Year 0) and Year 1. We defined moderate to severe (mod-severe) AS as a transaortic maximal outflow velocity (Vmax)>3.5 m/s combined with aortic valve area (AVA)<1.0 cm2, otherwise non-severe AS. An hsTnT>14 ng/L was high according to assay (Roche, Elecsys Troponin T hs on cobas e 601).

Linear multivariable regression model examined the association of hsTnT levels to clinical and echocardiographic variables.

Cox multivariable regression model evaluated competing risks and hazard ratios (HR) of outcomes while adjusting for relevant variables, including a Framingham 10-years risk score of cardiovascular diseases. The competing risks were either ACM or AVE, i.e. the first of AVR, cardiovascular death and heart failure due to AS progression.

Results

At baseline, hsTnT was high in 26% (453/1739) patients; 25% (380/1529) in non-severe and 35% (73/210) in mod-severe AS. Relative TnT change over one year was 17% (mean 1.17, SD 1.01); 15% in non-severe vs. 32% in mod-severe AS, and neither associated to AS severity, hsTnT at baseline or lipid-lowering treatment.

In multivariable linear regression analysis, there were significant correlations between hsTnT at baseline and age, male gender, creatinine, left ventricular mass index and BMI (all p<0.001, R-square=0.42), but not with AS severity.

In multivariable Cox regression analyses, a high hsTnT at baseline was associated with AVE 1.61 [95% CI 1.29–1.99]. In contrast, hsTnT at baseline was not associated to all-cause mortality (see figure).

Conclusions

In asymptomatic AS patients without severe AS, high-sensitive Troponin T is not associated with AS severity in cross-sectional analyses, and its levels do not change substantially during one year of follow-up. However, patients with hsTnT >14 ng/l had a sixty percent higher independent risk of subsequent aortic valve events.

Multivariable Cox regression

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Acknowledgements: Main sponsor (SEAS): MSD Singapore Company, LLC, partnership between Merck & Co. Inc. and Schering-Plough Corporation. Blood analysis sponsor: Roche

P3779NT-proBNP adds incremental predictive information on incident atrial fibrillation in patients with asymptomatic aortic stenosis

Background

Incident atrial fibrillation (AF) marks an adverse shift in the prognosis of patients with aortic stenosis (AS). Identifying risk factors for AF is therefore of paramount importance for timely intervention in patients with AS. In patients without AS, brain natriuretic peptides (BNP) is a well-established biomarker for left ventricular pressure overload on the pathway to heart failure and atrial fibrillation. However, a potential role of NT-proBNP to predict risk of new-onset AF in asymptomatic patients with mild to moderate AS is not well studied.

Methods

We included 1,434 patients with mild to moderate AS from the SEAS Study (Simvastatin and Ezetimibe in Aortic Stenosis) without AF or clinically overt heart failure at baseline. The primary endpoint for this substudy was time to incident AF, as determined by the first annual in-study 12-lead ECG with AF. Multivariable Cox model were adjusted for other important predictors of incident AF as selected by Bayesian statistics. Fine and Gray competing risk regression was used to evaluate the influence of all-cause mortality on selected predictor variables of incident AF.

Results

During a median follow-up of 4.3 years (range 0.1–6.9 years), incident AF occurred in 114 (6.1%) patients (13.8 per 1,000 person-years of follow-up), who at baseline were older (69±10 vs. 67±10 years, p<0.001), had larger systolic left atrial diameter (46±24 vs. 34±18 mm, p<0.001) and higher NT-proBNP level (286 [132; 613] vs. 154 [82; 297] pg/ml, p<0.001); but same left ventricular ejection fraction (66±6 mm vs. 67±6, p=0.4). In multivariable Cox regression, adjusted for age, circumferential end-systolic stress, left atrial volume and ECG PR interval, Ln(NT-proBNP) was associated with higher risk of new-onset AF (HR: 1.9 [95% CI: 1.6–2.3], p<0.001). Similar results were found when using Fine and Gray estimates with all-cause mortality (HR: 2.0 [95% CI: 1.7–2.4], p<0.001 (Figure, panel A). NT-proBNP level added incremental predictive information on incident AF over the other important, as selected by Bayesian statistics, predictor variables (C-index 0.81, p<0.001, Figure, panel B). There was no interaction with aortic valve area (p>0.05).

Figure 1

Conclusions

In patients with asymptomatic aortic stenosis and sinus rhythm at baseline, NT-proBNP levels were significantly higher in patients who subsequently developed AF. NT-proBNP significantly improved prognostic information of incident AF over other important predictor variables. This supports the notion that incident AF is a marker of left ventricular pressure overload and possibly a novel marker of timely intervention with aortic valve replacement.

P3835Improvement of myocardial energetic efficiency during treatment in hypertensive patients: the life study

Background

Myocardial energetic efficiency (MEE) per unit of left ventricular (LV) mass significantly predicts composite of cardiovascular (CV) events in treated hypertensive patients and specifically heart failure in an event-free population-based cohort with normal ejection fraction, independently of LV hypertrophy (LVH).

Purpose

To investigate whether MEEi changes over time in treated hypertensive patients, and whether different treatments have different effects.

Methods

From the Losartan Intervention For Endpoint study (LIFE Echo Sub-study) we selected 744 hypertensive patients (age 66±7 years; 45% women) with LVH at ECG, without atrial fibrillation, previous or incident myocardial infarction and with normal echocardiographic ejection fraction (>50%). MEE was estimated as the ratio of stroke work to the “double” product of heart rate times systolic blood pressure (BP), simplified as the ratio of stroke volume to heart rate, as previously reported. MEE was normalized for LVM (MEEi) and analyzed in quartiles at baseline and at the end treatment, according to an “intention-to-treat” protocol.

Results

Age and proportion of women were not significantly different from the highest to the lowest quartiles (from 65±7 to 66±7 years, p for trend=0.352; from 45% to 42%, p=0.946, respectively), whereas diastolic blood pressure (from 97±8 to 100±9 mmHg, p=0.006), prevalence of obesity (from 14 to 31%, p=0.001) and diabetes (from 4 to 14%, 0.004) progressively increased. Prevalence of concentric LV geometry and echocardiographic LVH also progressively increased from the highest to the lowest quartile (from 14 to 70%, and 61 to 90%, both p<0.0001). MEEi increased over time (p<0.007), independently of initial diastolic BP, diabetes and obesity, significantly more in patients treated with atenolol than with losartan (p<0.0001) (Figure), due to both increased stroke volume and decreased heart rate (both p<0.0001).

Figure 1

Conclusions

In a randomized clinical study, MEEi improves with anti-hypertensive therapy. Improvement is more evident in patients with atenolol than with losartan-based treatment, possibly providing pathophysiologic explanation of the comparable performance in prevention of ischemic heart disease previously reported in the LIFE study.

A prediction of the renal and cardiovascular efficacy of aliskiren in ALTITUDE using short-term changes in multiple risk markers

INTRODUCTION

We recently developed and validated in existing trials a novel algorithm (PRE score) to predict long-term drug efficacy based on short-term (month-6) drug-induced changes in multiple risk markers. To show the value of the PRE score for ongoing and planned clinical trials, we here report the predicted long-term cardio-renal efficacy of aliskiren in type 2 diabetes, which was investigated in the ALTITUDE trial, but unknown at the time this study was conducted.

METHODS

We established the relation between multiple risk markers and cardio-renal endpoints (as defined in ALTITUDE) using a background database from past clinical trials. The short-term effect of aliskiren on multiple risk markers was taken from the AVOID trial. A PRE score was developed by multivariate Cox analysis in the background population and was then applied to the baseline and month-6 measurements of the aliskiren treatment arm of the AVOID trial to predict cardio-renal risk. The net risk difference at these time-points, after correction for placebo effects, was taken to indicate the estimated long-term cardio-renal risk change.

RESULTS

Based on the PRE score, we predicted that aliskiren treatment in ALTITUDE would confer a relative risk change of -7.9% (95% CI -2.5 to -13.4) for the cardio-renal endpoint, a risk change of -5.1% (-1.2 to -9.0) for the CV endpoint and a non-significant risk change of -19.9% (-42.1 to +2.1) for the renal endpoint.

CONCLUSIONS

PRE score estimations suggested that aliskiren has only a marginal additive protective effect on cardio-renal endpoints. These predictions were validated by the results of the ALTITUDE trial, confirming the potential of the PRE score to prospectively predict drug efficacy on cardio-renal outcomes.

Impact of overweight and obesity on cardiac benefit of antihypertensive treatment

BACKGROUND AND AIMS

Increased body mass index (BMI) has been associated with increased cardiovascular morbidity and mortality in hypertension. Less is known about the impact of BMI on improvement in left ventricular (LV) structure and function during antihypertensive treatment.

METHODS AND RESULTS

Annual BMI, echocardiograms and cardiovascular events were recorded in 875 hypertensive patients with LV hypertrophy during 4.8 years randomized treatment in the Losartan Intervention For Endpoint reduction in hypertension (LIFE) echocardiography substudy. Patients were grouped by baseline BMI into normal (n = 282), overweight (n = 405), obese (n = 150) and severely obese groups (n = 38) (BMI ≤24.9, 25.0-29.9, 30.0-34.9, and ≥35.0 kg/m(2), respectively). At study end, residual LV hypertrophy was present in 54% of obese and 79% of severely obese patients compared to 31% of normal weight patients (both p < 0.01). In regression analyses, adjusting for initial LV mass/height(2.7), higher BMI predicted less LV hypertrophy reduction and more reduction in LV ejection fraction (both p < 0.05), independent of blood pressure reduction, diabetes and in-study weight change. During follow-up, 91 patients suffered cardiovascular death, myocardial infarction or stroke. In Cox regression analysis 1 kg/m(2) higher baseline BMI predicted a 5% higher rate of cardiovascular events and 10% higher cardiovascular mortality over 4.8 years (both p < 0.05).

CONCLUSIONS

In hypertensive patients in the LIFE study, increased BMI was associated with less reduction of LV hypertrophy and less improvement in LV systolic function which may contribute to the observed higher cardiovascular event rate of treated hypertensive patients.

Serum uric acid is associated with new-onset diabetes in hypertensive patients with left ventricular hypertrophy: The LIFE Study

BACKGROUND

It is unclear whether serum uric acid (SUA) is associated with development of new-onset diabetes (NOD) in patients with hypertension and left ventricular hypertrophy (LVH). The aim of the present investigation was to test the hypothesis that SUA predicts development of NOD in these patients.

METHODS

In the Losartan Intervention For Endpoint reduction in hypertension (LIFE) study, a double-masked, parallel-group design, 9,193 patients with hypertension and electrocardiographic LVH were randomized to losartan- or atenolol-based antihypertensive treatment and followed for a mean of 4.9 years. At baseline, 7,489 patients with available SUA measurements did not have diabetes mellitus and were thus at risk of its development during the study. We used Cox regression analyses to investigate whether SUA predicted development of NOD.

RESULTS

NOD developed in 522 of 7,489 patients. The association between baseline SUA and development of NOD was significant (hazard ratio (HR) 1.29 per s.d. (1.3 mg/dl), 95% confidence interval (CI) 1.18-1.42, P < 0.001) after adjustment for treatment with losartan vs. atenolol, baseline serum glucose, urinary albumin/creatinine ratio, estimated glomerular filtration rate and Framingham risk score, time-varying systolic and diastolic blood pressure, and time-varying LVH by Cornell voltage-duration product and Sokolow-Lyon voltage. In parallel analyses, baseline quartiles of SUA were significantly associated with increasing NOD (HR 1.28, 95% CI 1.18-1.40, P < 0.001). Time-varying SUA was also associated with NOD (HR 1.10 per s.d. [1.3 mg/dl], 95% CI 1.02-1.19, P = 0.015).

CONCLUSION

Our analysis suggests that SUA is an independent risk marker for NOD in hypertensive patients with LVH.

Clustered metabolic abnormalities blunt regression of hypertensive left ventricular hypertrophy: the LIFE study

BACKGROUND AND AIMS

Clusters of metabolic abnormalities resembling phenotypes of metabolic syndrome predicted outcome in the LIFE study, independently of single risk markers, including obesity, diabetes and baseline ECG left ventricular hypertrophy (LVH). We examined whether clusters of two or more metabolic abnormalities (MetAb, including obesity, high plasma glucose without diabetes, low HDL-cholesterol) in addition to hypertension were associated to levels of ECG LVH reduction comparable to that obtained in hypertensive subjects without or with only one additional metabolic abnormality (no-MetAb).

METHODS AND RESULTS

We studied 5558 non-diabetic participants without MetAb (2920 women) and 1235 with MetAb (751 women) from the LIFE-study cohort. MetAb was defined by reported LIFE criteria, using partition values from the ATPIII recommendations. Time-trends of Cornell voltage-duration product (CP) over 5 years was assessed using a quadratic polynomial contrast, adjusting for age, sex, prevalent cardiovascular disease and treatment arm (losartan or atenolol). At baseline, despite similar blood pressures, CP was greater in the presence than in the absence of MetAb (p<0.0001). During follow-up, despite similar reduction of blood pressure, CP decreased less in patients with than in those without MetAb, even after adjustment for the respective baseline values (both p<0.002). Losartan was more effective than atenolol in reducing CP independently of MetAb.

CONCLUSIONS

Clusters of metabolic abnormalities resembling phenotypes of metabolic syndrome are related to greater initial ECG LVH in hypertensive patients with value of blood pressure similar to individuals without metabolic abnormalities, and are associated with less reduction of ECG LVH during antihypertensive therapy, potentially contributing to the reported adverse prognosis of metabolic syndrome.

Impact of diabetes on treatment-induced changes in left ventricular structure and function in hypertensive patients with left ventricular hypertrophy. The LIFE study

BACKGROUND AND AIM

Diabetes is associated with left ventricular hypertrophy (LVH) and impaired systolic function in hypertensive patients, but less is known about its impact on LVH regression and functional improvement during antihypertensive treatment.

METHODS AND RESULTS

We performed annual echocardiography in 730 non-diabetic and 93 diabetic patients (aged 55-80 years) with hypertension and electrocardiographic LVH during 4.8-year losartan- or atenolol-based treatment in the Losartan Intervention For Endpoint reduction in hypertension (LIFE) study. Baseline mean blood pressure (BP) and LV mass did not differ between groups. Diabetic patients had higher body mass index and pulse pressure, and lower LV ejection fraction, midwall shortening, stress-corrected midwall shortening, and estimated glomerular filtration rate (all p<0.05), and were more likely to have albuminuria. Despite comparable BP reduction in diabetic and non-diabetic groups during treatment (33/18 vs. 28/16mmHg (ns)), diabetes was associated with higher prevalence of persistent LVH (47 vs. 39%, p<0.05). In multivariate analyses, diabetes independently predicted less LV mass reduction and less improvement in stress-corrected LV midwall shortening (both p<0.01).

CONCLUSION

Among hypertensive patients with LVH, diabetes is associated with more residual LVH and less improvement in systolic LV function by echocardiography over 4.8 years of antihypertensive treatment.

Reduction in albuminuria translates to reduction in cardiovascular events in hypertensive patients with left ventricular hypertrophy and diabetes

In type 2 diabetes the degree of albuminuria is strongly related to progression of diabetic renal disease, as well as to the risk for cardiovascular complications. If normoalbuminuria is maintained, the risk of diabetic nephropathy is very low. In individuals with microalbuminuria, the rate of decline in glomerular filtration rate is closely related to the degree of albuminuria, and regression to normoalbuminuria slows down the rate of decline in renal function. Data from the LIFE-diabetes subgroup showed that levels of albuminuria well below what is usually defined as microalbuminuria, strongly predicted risk for cardiovascular complications. This indicates that when albuminuria is used as a risk predictor for cardiovascular events, so called normal values should be redefined. Traditional values for normo-micro-macroalbuminuria are primarily defined as predictors for the risk of development of diabetic nephropathy. In the LIFE-diabetes subgroup we found that reduction in albuminuria was more pronounced in losartan-based as compared with atenolol-based treatment. The benefit in favor of losartan was partly related to its major influence on albuminuria. Individuals with the highest baseline values of albuminuria had the greatest benefit in terms of reduction in cardiovascular morbidity and mortality on losartan as compared with atenolol. The level of albuminuria during treatment was closely related to the risk for cardiovascular events. We conclude that tiny amounts of albuminuria, well below traditional levels for microalbuminuria, predict cardiovascular morbidity and mortality. Reduction in albuminuria during treatment translates to reduction in cardiovascular events. Monitoring of albuminuria should be an integrated part of management of hypertension in diabetic as well as nondiabetic patients.

Change in pulse pressure/stroke index in response to sustained blood pressure reduction and its impact on left ventricular mass and geometry changes: the life study

BACKGROUND

In cross-sectional data in hypertensive subjects, brachial pulse pressure (PP)/Doppler stroke index (SVi), (PP/SVi) correlates weakly but significantly with left ventricular (LV) mass and relative wall thickness (RWT).

METHODS

In the Losartan Intervention For End-point reduction in hypertension (LIFE) study, we evaluated the impact of antihypertensive treatment on change of PP/SVi as raw indicator of systemic arterial stiffness, and further explored the impact of the change in PP/SVi on the change in LV mass and RWT.

RESULTS

Compared to baseline, mean PP/SVi reduction was -13% at year 1, -15% at year 2, and -16% at year 3 follow-up, and was sustained through year 4 and year 5 follow-ups; change in PP/SVi was related to increased SVi and decreased PP during the annual follow-ups, but not to LV mass change. Restricting analyses to the first two follow-ups to ensure highest statistical power, age >65 and diabetes were associated with higher PP/SVi at baseline and throughout follow-ups; black participants and women had baseline PP/SVi mean values comparable with those of their counterparts, showed blunted PP/SVi reduction after 1 year, but differences became smaller and not statistically significant at year 2 follow-up. Losartan- or atenolol-based treatments were associated with comparable reduction of PP/SVi. At year 2 follow-up, reduced PP/SVi was associated with greater reductions in mean blood pressure (BP) and heart rate and greater increase in SVi, but not with lower LV mass; RWT was lower with lower PP/SVi at year 2 follow-up.

CONCLUSIONS

Reduction in PP/SVi by long-term antihypertensive treatment did not have significant impact on change in LV mass index, but correlated with LV remodeling toward eccentric geometry.

Combination of the electrocardiographic strain pattern and albuminuria for the prediction of new-onset heart failure in hypertensive patients: the LIFE study

BACKGROUND

Although albuminuria and the electrocardiographic (ECG) strain pattern each predict development of heart failure (HF), whether combining albuminuria and strain improves prediction of new HF is unclear.

METHODS

The relation of ECG strain and albuminuria to new-onset HF was examined in 7,786 hypertensive patients with no history of HF, who were randomly assigned to treatment with losartan or atenolol. Albuminuria was defined by a urine albumin/creatinine ratio >30.94 mg/g.

RESULTS

During a mean follow-up of 4.7 +/- 1.1 years, new-onset HF occurred in 231 patients (3.0%). Five-year HF rate was highest when both strain and albuminuria were present (10.4%), intermediate when only ECG strain (8.0%) or albuminuria (4.9%) was present, and lowest when neither strain nor albuminuria was present at baseline (1.8%, P < 0.0001). In Cox multivariable analyses, controlling for HF risk factors, treatment assignment and baseline severity of ECG left ventricular hypertrophy (LVH) by both Sokolow-Lyon voltage and Cornell product, ECG strain and albuminuria remained significant predictors of incident HF, with the presence of both strain and albuminuria associated with the highest risk (HR 2.8, 95% CI 1.8-4.4) and the presence of only strain (HR 2.6, 95% CI 1.7-4.0) or albuminuria (HR 2.1, 95% CI 1.5-2.8) with intermediate risk of new HF compared with the absence of both strain and albuminuria.

CONCLUSIONS

The combination of albuminuria and ECG strain identifies hypertensive patients at an increased risk of developing HF in the setting of aggressive blood pressure lowering, independent of treatment modality and of other risk factors for HF.

Clusters of metabolic risk factors predict cardiovascular events in hypertension with target-organ damage: the LIFE study

The relation of metabolic syndrome (MetS) with cardiovascular outcome may be less evident when preclinical cardiovascular disease is present. We explored, in a post hoc analysis, whether MetS predicts cardiovascular events in hypertensive patients with electrocardiographic left ventricular hypertrophy (ECG-LVH) in the Losartan Intervention For Endpoint (LIFE) reduction in hypertension study. MetS was defined by >or=2 risk factors plus hypertension: body mass index >or=30 kg/m(2), high-density lipoprotein (HDL)-cholesterol <1.0/1.3 mmol/l (<40/50 mg/dl) (men/women), glucose >or=6.1 mmol/l (>or=110 mg/dl) fasting or >or=7.8 mmol/l (>or=140 mg/dl) nonfasting or diabetes. Cardiovascular death and the primary composite end point (CEP) of cardiovascular death, stroke and myocardial infarction were examined. In MetS (1,591 (19.3%) of 8,243 eligible patients), low HDL-cholesterol (72%), obesity (77%) and impaired glucose (73%) were similarly prevalent, with higher blood pressure, serum creatinine and Cornell product, but lower Sokolow-Lyon voltage (all P<0.001). After adjusting for baseline covariates, hazard ratios for CEPs and cardiovascular death (4.8+/-1.1 years follow-up) were 1.47 (95% confidence interval (CI), 1.27-1.71)- and 1.73 (95% CI, 1.38-2.17)-fold higher with MetS (both P<0.0001), and were only marginally reduced when further adjusted for diabetes, obesity, low HDL-cholesterol, non-HDL-cholesterol, pulse pressure and in-treatment systolic blood pressure and heart rate. Thus, MetS is associated with increased cardiovascular events in hypertensive patients with ECG-LVH, independently of single cardiovascular risk factors.

Impairment of cardiac function in hypertensive patients with Type 2 diabetes: a LIFE study

AIMS

Type 2 diabetic patients with hypertension have an increased left ventricular (LV) mass and impaired cardiac function compared to hypertensive patients without diabetes. However, it is unknown if the impaired cardiac function can be explained solely by LV hypertrophy, or is independently related to diabetes. The aim of the present study was to compare LV function between diabetic and non-diabetic hypertensive patients with electrocardiographic LV hypertrophy.

METHODS

In 937 patients participating in the LIFE echocardiographic substudy, all echocardiograms were centrally evaluated by a core reading centre measuring LV mass, systolic and diastolic LV function. Known diabetes was present in 105 patients.

RESULTS

Left ventricular mass was similar in diabetic and non-diabetic patients. Endocardial systolic LV function, estimated by LV ejection fraction, was reduced and indices of midwall systolic LV function were impaired in the diabetic patients. Diastolic LV filling pattern was impaired and arterial stiffness, measured by pulse pressure/stroke index, was increased in diabetic patients.

CONCLUSIONS

Systolic and diastolic LV function in hypertensive patients with electrocardiographic LV hypertrophy and diabetes are impaired independent of LV mass, most likely reflecting the adverse effects of diabetes per se.

Markers of collagen synthesis is related to blood pressure and vascular hypertrophy: a LIFE substudy

Cardiac fibrosis and high levels of circulating collagen markers has been associated with left ventricular (LV) hypertrophy. However, the relationship to vascular hypertrophy and blood pressure (BP) load is unclear. In 204 patients with essential hypertension and electrocardiographic LV hypertrophy, we measured sitting BP, serum collagen type I carboxy-terminal telopeptide (ICTP) reflecting degradation, procollagen type I carboxy-terminal propeptide (PICP) reflecting synthesis and LV mass by echocardiography after 2 weeks of placebo treatment and after 1 year of antihypertensive treatment with a losartan- or an atenolol-based regimen. Furthermore, we measured intima-media thickness of the common carotid arteries (IMT), minimal forearm vascular resistance (MFVR) by plethysmography and ambulatory 24-h BP in around half of the patients. At baseline, PICP/ICTP was positively related to IMT (r=0.24, P<0.05), MFVR(men) (r=0.35, P<0.01), 24-h systolic BP (r=0.24, P<0.05) and 24-h diastolic BP (r=0.22, P<0.05), but not to LV mass. After 1 year of treatment with reduction in systolic BP (175+/-15 vs 151+/-17 mmHg, P<0.001) and diastolic BP (99+/-8 vs 88+/-9 mmHg, P<0.001), ICTP was unchanged (3.7+/-1.4 vs 3.8+/-1.4 microg/l, NS) while PICP (121+/-39 vs 102+/-29 microg/l, P<0.001) decreased. The reduction in PICP/ICTP was related to the reduction in sitting diastolic BP (r=0.31, P<0.01) and regression of IMT (r=0.37, P<0.05) in patients receiving atenolol and to reduction in heart rate in patients receiving losartan (r=0.30, P<0.01). In conclusion, collagen markers reflecting net synthesis of type I collagen were positively related to vascular hypertrophy and BP load, suggesting that collagen synthesis in the vascular wall is increased in relation to high haemodynamic load in a reversible manner.

Regression of electrocardiographic left ventricular hypertrophy predicts regression of echocardiographic left ventricular mass: the LIFE study

The electrocardiogram (ECG) is widely used for detection of left ventricular hypertrophy (LVH). However, whether changes in ECG LVH during antihypertensive therapy predict changes in LV mass remains unclear. Baseline and year-1 ECGs and echocardiograms were assessed in 584 hypertensive patients with ECG LVH by Sokolow-Lyon or Cornell voltage-duration product criteria at entry into the Losartan Intervention For Endpoint reduction in hypertension (LIFE) echocardiographic substudy. A >/=25% decrease in Cornell product defined regression of ECG LVH; a <25% decrease defined no significant regression; and an increase defined progression of ECG LVH. Regression of echocardiographic LVH was defined by a >/=20% reduction in LV mass. After 1 year of therapy, 155 patients (27%) had regression of ECG LVH, 286 (49%) had no significant change, and 143 (25%) had progression of ECG LVH. Compared with patients with progression of ECG LVH, patients with no significant decrease and patients with regression of ECG LVH had stepwise greater absolute decreases in LV mass (-16+/-33 vs -29+/-37 vs -32+/-41 g, P<0.001), greater percent reductions in LV mass (-5.7+/-14.6 vs -11.3+/-13.6 vs -12.3+/-15.6%, P<0.001), and were more likely to decrease LV mass by >/=20% (11.2 vs 24.8 vs 36.1%, P<0.001), even after adjusting for possible effects of baseline and change in systolic and diastolic pressures. Compared with progression of ECG LVH, regression of the Cornell product ECG LVH is associated with greater reduction in LV mass and a greater likelihood of regression of anatomic LVH.

Usefulness of the assessment of the appropriateness of left ventricular mass to detect left ventricular systolic and diastolic abnormalities in absence of echocardiographic left ventricular hypertrophy: the LIFE study

Conventional definitions of left ventricular (LV) hypertrophy do not account for interindividual differences in loading conditions. We may define LV mass as inappropriately high when exceeding 128% of theoretical values predicted by gender, height(2.7), and stroke work, which explain up to 82% of the variability of LV mass in normal reference subjects. In 652 participants in the Losartan Intervention For Endpoint reduction in hypertension study without clinically overt cardiovascular disease or diabetes, we investigated whether inappropriately high LV mass is associated with relevant LV abnormalities independent of traditional definition of LV hypertrophy (ie, LV mass index >116 g/m(2) in men and >104 g/m(2) in women). The study sample was divided into three groups: patients with inappropriately high LV mass but without LV hypertrophy were compared to patients with LV hypertrophy and to patients with appropriate LV mass and without LV hypertrophy. Patients with inappropriately high but nonhypertrophic LV mass had higher body mass index and relative wall thickness, and lower LV myocardial systolic function, than patients with appropriate LV mass or patients with LV hypertrophy. In multivariate analyses, inappropriately high LV mass was independently associated with lower myocardial systolic function independent of LV hypertrophy and other covariates. Inappropriately high LV mass was also associated with prolonged isovolumic relaxation time and lower mitral E/A ratio independent of covariates. In conclusion, inappropriately high LV mass was associated with relevant, often preclinical, manifestations of cardiac disease in the absence of traditionally defined echocardiographic LV hypertrophy and concentric geometry.

Impact of age on left ventricular hypertrophy regression during antihypertensive treatment with losartan or atenolol (the LIFE study)

To assess the influence of age on changes in left ventricular (LV) mass and geometry during antihypertensive treatment, we related age to clinical and echocardiographic findings before and after 4 years of antihypertensive treatment in a subset of 560 hypertensive patients without known concurrent disease in the Losartan Intervention For Endpoint reduction in hypertension (LIFE) study, which randomized patients to blinded losartan- or atenolol-based treatment. Patients >/=65 years (older group) included more women and patients with isolated systolic hypertension or albuminuria (all P<0.05). Compared to patients <65 years, older patients had higher pulse pressure, LV mass, and prevalence of concentric hypertrophy at baseline (78 vs 69 mmHg, 234 vs 224 g, and 28 vs 16%, respectively, all P<0.01), while the mean blood pressure did not differ. Over 4 years, reductions in LV mass and the mean blood pressure were similar in both groups, but older patients more often had residual hypertrophy (31 vs 15%, P<0.001) with a preponderance of eccentric geometry. In multivariate analysis of 4-year change in LV mass controlling for baseline mass, larger hypertrophy reduction was associated with losartan treatment, while age, gender, body mass index, and 4-year change in pulse pressure and albuminuria did not enter (Multiple R (2)=0.40, P<0.001). Thus, in up-to-80-year-old hypertensive patients with left ventricular hypertrophy, age did not significantly attenuate hypertrophy reduction during antihypertensive treatment, although residual hypertrophy was more prevalent in older patients as a consequence of higher initial LV mass.

Albuminuria predicts cardiovascular events independently of left ventricular mass in hypertension: a LIFE substudy

We wanted to investigate whether urine albumin/creatinine ratio (UACR) and left ventricular (LV) mass, both being associated with diabetes and increased blood pressure, predicted cardiovascular events in patients with hypertension independently. After 2 weeks of placebo treatment, clinical, laboratory and echocardiographic variables were assessed in 960 hypertensive patients from the LIFE Echo substudy with electrocardiographic LV hypertrophy. Morning urine albumin and creatinine were measured to calculate UACR. The patients were followed for 60+/-4 months and the composite end point (CEP) of cardiovascular (CV) death, nonfatal stroke or nonfatal myocardial infarction was recorded. The incidence of CEP increased with increasing LV mass (below the lower quartile of 194 g to above the upper quartile of 263 g) in patients with UACR below (6.7, 5.0, 9.1%) and above the median value of 1.406 mg/mmol (9.7, 17.0, 19.0%(***)). Also the incidence of CV death increased with LV mass in patients with UACR below (0, 1.4, 1.3%) and above 1.406 mg/mmol (2.2, 6.4, 8.0%(**)). The incidence of CEP was predicted by logUACR (hazard ratio (HR)=1.44(**) for every 10-fold increase in UACR) after adjustment for Framingham risk score (HR=1.05(***)), history of peripheral vascular disease (HR=2.3(*)) and cerebrovascular disease (HR=2.1(*)). LV mass did not enter the model. LogUACR predicted CV death (HR=2.4(**)) independently of LV mass (HR=1.01(*) per gram) after adjustment for Framingham risk score (HR=1.05(*)), history of diabetes mellitus (HR=2.4(*)) and cerebrovascular disease (HR=3.2(*)). (*)P<0.05, (**)P<0.01, (***)P<0.001. In conclusion, UACR predicted CEP and CV death independently of LV mass. CV death was predicted by UACR and LV mass in an additive manner after adjustment for Framingham risk score and history of CV disease.

Association of left bundle branch block with left ventricular structure and function in hypertensive patients with left ventricular hypertrophy: the LIFE study

Electrocardiographic (ECG) left bundle branch block (LBBB) is associated with left ventricular hypertrophy (LVH), but its relation to left ventricular (LV) geometry and function in hypertensive patients with ECG LVH is unknown. Echocardiograms were performed in 933 patients (548 women, mean age 66+/-7 years) with essential hypertension and LVH by baseline ECG in the Losartan Intervention For Endpoint reduction in hypertension (LIFE) study. LBBB, defined by Minnesota code 7.1, was present in 47 patients and absent in 886 patients. Patients with and without LBBB were similar in age, gender, body mass index, blood pressure, prevalence of diabetes, and history of myocardial infarction. Despite similarly elevated mean LV mass (126+/-25 vs 124+/-26 g/m(2)) and relative wall thickness (0.41+/-0.07 vs 0.41+/-0.07, P=NS), patients with LBBB had lower LV fractional shortening (30+/-6 vs 34+/-6%), ejection fraction (56+/-10 vs 61+/-8%), midwall shortening (14+/-2 vs 16+/-2%), stress-corrected midwall shortening (90+/-13 vs 97+/-13%) (all P<0.001), and lower LV stroke index (38+/-7 vs 42+/-9 ml/m(2)) (P<0.05). Patients with LBBB also had reduced LV inferior wall and lower mitral E/A ratio (0.75+/-0.18 vs 0.87+/-0.38) (all P<0.05). The above univariate results were confirmed by multivariate analyses adjusted for gender, age, blood pressures, height, weight, body mass index, heart rate, and LV mass index. Among hypertensive patients at high risk because of ECG LVH, the presence of LBBB identifies individuals with worse global and regional LV systolic function and impaired LV relaxation without more severe LVH by echocardiography.

Long-term plasma catecholamines in patients with hypertension and left ventricular hypertrophy treated with losartan or atenolol: ICARUS, a LIFE substudy

Hypertension is a major risk factor for morbidity and mortality. Plasma catecholamines are linked to the pathogenesis of hypertension. Pharmacological intervention, including treatment with beta-blockers, reduces cardiovascular mortality and morbidity. In the Losartan Intervention For Endpoint reduction in hypertension (LIFE) study, the angiotensin receptor blocker losartan significantly reduced cardiovascular end points compared to the beta-blocker atenolol. Thus, for the first time, one drug was shown to be superior to another in hypertension. The present substudy examined the effects of atenolol vs losartan treatment on plasma catecholamines at rest and during hyperinsulinaemia in a cohort of 86 LIFE patients. Plasma adrenaline increased significantly from placebo treatment at baseline to year 1 of treatment (P<0.0001), and also during hyperinsulinaemia (P<0.0001). Plasma noradrenaline did not change significantly from placebo treatment at baseline to year 1, but increased significantly during hyperinsulinaemia both at baseline and at year 1 (P<0.0001 for both). There were no differences in plasma catecholamines or the relative changes between the two treatment arms at any stage. In a subset of 42 patients examined also at years 2 and 3, these findings were confirmed during long-term treatment. Thus, losartan had an effect on plasma catecholamines comparable to that with the beta-blocker atenolol in patients with hypertension and left ventricular hypertrophy at rest and during hyperinsulinaemia. We find it unlikely that a difference in sympathetic activity explains the outcome benefits of losartan over atenolol in the LIFE study.

24-h Ambulatory blood pressure in patients with ECG-determined left ventricular hypertrophy: left ventricular geometry and urinary albumin excretion—a LIFE substudy

This study was undertaken to evaluate the relationships among left ventricular (LV) geometric patterns and urinary albumin excretion in patients with hypertension and electrocardiographic (ECG) LV hypertrophy. In 143 patients with stage II-III hypertension, 24-h ambulatory blood pressure (BP) monitoring, single urine albumin determination, and echocardiography were performed after 14 days of placebo treatment. Mean age was 68+/-7 years, 35% were women, body mass index was 28+/-5 kg/m(2), LV mass index (LVMI) was 125+/-26 g/m(2), and 24% had microalbuminuria. The mean office BP was 176+/-15/99+/-8 mmHg and the mean daytime ambulatory BP was 161+/-18/92+/-12 mmHg. Ambulatory BP, but not office BP, was higher among albuminuric compared to normoalbuminuric patients. In patients with established hypertension, daytime pulse pressure and office BP were different in the four patterns of LV geometry, with the highest pressure in those with abnormal geometry. Furthermore, microalbuminuria was more frequent in hypertensive patients with LV hypertrophy than in those with either normal geometry or concentric remodelling. White coat hypertensives (10%) showed lower LVMI and no microalbuminuria compared to patients with established hypertension. There were no differences in the prevalence of nondippers (26%) among the four LV geometric patterns or in microalbuminuria. In conclusion, increased daytime pulse pressure and office BP were associated with increased prevalence of abnormal LV geometry. Microalbuminuria was more frequent in groups with concentric and eccentric LV hypertrophy. Ambulatory BP, but not office BP, was higher in albuminuric than normoalbuminuric patients. With regard to the relationship among BP, LV geometric patterns, and urine albumin excretion in this population, 24-h ambulatory BP did not provide additional information beyond the office BP.

Sex-related difference in regression of left ventricular hypertrophy with antihypertensive treatment: the LIFE study

While left ventricular (LV) structure and function differ between hypertensive women and men, it remains unclear whether sex affects regression of LV hypertrophy with antihypertensive treatment. We analysed paired echocardiograms in 500 men and 347 women enrolled in the Losartan Intervention For Endpoint reduction in hypertension (LIFE) study at baseline and after 12 months of antihypertensive treatment with either losartan or atenolol. At enrollment, 177 women and 242 men were randomized to losartan-based treatment and 161 women and 247 men were randomized to atenolol-based treatment (sex difference=NS). After 12 months of antihypertensive treatment, blood pressure was lowered similarly in women (152/83 from 174/97 mmHg) and men (149/85 from 173/99 mmHg; both P<0.001, sex difference=NS), without significant change in body weight in either sex. Cardiac output and pulse pressure/stroke volume were equivalently reduced in both sexes (-0.2 vs -0.1 l/min and both -0.20 mmHg/ml/m(2), respectively; both P=NS). Absolute LV mass change after 12 months of antihypertensive treatment was greater in men than in women (-30 vs -24 g, P=0.01). However, after adjusting for baseline LV mass and randomized study treatment, LV mass reduction was greater in women than in men (-33 vs -23 g, P=0.001). LV mass regression was greater in women, by 8.0+/-2.8 g, after adjusting for baseline LV mass and randomized study treatment. After consideration of baseline LV mass and randomized study treatment, antihypertensive treatment regressed LV hypertrophy more in women. Further studies are needed to identify the mechanisms and prognostic implications of this sex-related difference.

Impact of valvular regurgitation on left ventricular geometry and function in hypertensive patients with left ventricular hypertrophy: the LIFE study

Mild-to-moderate aortic and mitral regurgitation are frequently detected by echocardiogram in asymptomatic hypertensive patients. Our goal was to assess the prevalence and impact of mild-to-moderate mitral and/or aortic regurgitation on left ventricular (LV) structure and function in patients with hypertension and LV hypertrophy (LVH). Hypertensive patients with ECG LVH enrolled in the Losartan Intervention For Endpoint reduction in hypertension (LIFE) echocardiography substudy were evaluated. Among 939 patients with needed LV measurements and Doppler data, 242 had mild (1+) valvular regurgitation, and 51 patients had moderate (2+ or 3+) regurgitation of one or both valves. In analyses adjusting for gender, patients with mild mitral and/or aortic regurgitation had larger LV internal dimensions (5.25 vs 5.33 cm, P<0.05), higher LV mass indexed for body surface area (122 vs 125 g/m(2), P<0.05) or height(2.7) (55.4 vs 57.3, P<0.05), and larger left atrial diameter. Patients with moderate regurgitation of one or both valves had larger LV chambers (5.25 vs 5.9 cm, P<0.001), greater mean LV mass (232 vs 248 g, P<0.001) and LV mass indexed for body surface area or height(2.7), and higher Doppler stroke volume. Patients with moderate valvular regurgitation also had a higher prevalence of LVH due to an increased prevalence of eccentric LVH. There were no differences among groups defined by the presence and severity of valvular regurgitation in cardiac output, total peripheral resistance, or pulse pressure/stroke volume, indicating that the observed inter-group differences in LV geometry were not due to differences in the haemodynamic severity of hypertension. Hypertensive patients with mild-to-moderate mitral or aortic valvular insufficiency have additional LV structural and functional changes that may affect prognosis.

Is inappropriate left ventricular mass related to neurohormonal factors and/or arterial changes in hypertension? a LIFE substudy

We investigated whether inappropriately high left ventricular (LV) mass, defined as observed LV mass exceeding the level of individual LV mass predicted from gender, height, and stroke work, may be associated with an imbalance between growth-promoting and growth-inhibitory factors and/or structural vascular changes. In 53 patients with hypertension and electrocardiographic LV hypertrophy, 24-h ambulatory blood pressure (BP); echocardiographic LV mass, stroke volume and stroke work; minimal forearm vascular resistance (MFVR); and intima-media cross-sectional area in common carotid arteries (IMA) were evaluated after 2 weeks of placebo treatment. Serum insulin, plasma epinephrine, norepinephrine, endothelin, angiotensin II, aldosterone, and brain natriuretic peptide (BNP) were also measured. High observed LV mass was related to high IMA (r=0.46, P<0.001), MFVR (in men: r=0.36, P<0.05), 24-h ambulatory systolic BP (r=0.30, P=0.06), and lower plasma angiotensin II (r=-0.33, P<0.05), but not to other circulating growth factors. Stroke work was similarly related to IMA (r=0.42, P<0.01), MFVR (in men: r=0.41, P<0.05), and plasma angiotensin II (r=-0.32, P<0.05). Inappropriate LV mass, identified by the ratio between observed LV mass and the value predicted for gender, height, and stroke work, was not significantly related to any of the arterial or neurohormonal variables. In this small series of older hypertensive patients, inappropriate LV mass was not significantly related to arterial changes or to measured circulating growth factors, although weak relations cannot be excluded. Alternatively, inappropriately high LV mass might be related to unmeasured factors such as local myocardial alterations in growth factors and/or genetic predisposition to develop excessive LV hypertrophy.

Association between vascular dysfunction and reduced myocardial flow reserve in patients with hypertension: a LIFE substudy

Impaired myocardial flow reserve (MFR) has been demonstrated in hypertension, and has been associated with peripheral vascular changes. We investigated whether MFR was impaired and associated with structural and/or functional vascular changes in hypertensive patients without evidence of coronary artery disease (CAD). We measured left ventricular (LV) mass index by echocardiography and MFR by positron emission tomography in 33 unmedicated, hypertensive patients with electrocardiographic LV hypertrophy without CAD, and 15 age- and gender-matched normotensive subjects. We also measured 24-h ambulatory blood pressure, minimal forearm vascular resistance (MFVR) by plethysmography, media:lumen ratio in isolated, subcutaneous resistance arteries by myography, intima-media cross-sectional area of the common carotid artery, and flow-mediated (FMD) and nitroglycerin-induced dilatation (NID) of the brachial artery by ultrasound. Compared to the controls, the patients had impaired MFR (2.4 (95% CI 1.95-2.8) vs 3.4 (2.7-4.2), P<0.01) due to increased resting myocardial blood flow (MBF) (0.82 (0.73-0.91) vs 0.65 (0.56-0.75) ml/g min), and decreased dipyridamole-stimulated MBF (1.80 (1.55-2.1) vs 2.3 (1.80-2.8) ml/g min, both P<0.05). The difference in resting MBF disappeared (80 (74-87) vs 86 (74-97) microl/kg mmHg, NS) when normalized for blood pressure and heart rate. MFR correlated negatively to median 24-h systolic blood pressure (r=-0.50, P<0.01) as well as to LV mass index (r=-0.45, P<0.05) and MFVR in men (r=-0.47, P<0.05), and positively to FMD (r=0.44, P<0.05) and NID (r=0.40, P<0.05). Hypertensive patients with electrocardiographic LV hypertrophy without CAD had impaired MFR associated with cardiovascular hypertrophy and vasodilatory dysfunction. This suggests that MFR is impaired by LV hypertrophy and structural/functional vascular damage in the coronary and noncoronary circulation.

Are left ventricular mass, geometry and function related to vascular changes and/or insulin resistance in long-standing hypertension? ICARUS: a LIFE substudy

Vascular hypertrophy and insulin resistance have been associated with abnormal left ventricular (LV) geometry in population studies. We wanted to investigate the influence of vascular hypertrophy and insulin resistance on LV hypertrophy and its function in patients with hypertension. In 89 patients with essential hypertension and electrocardiographic LV hypertrophy, we measured blood pressure; insulin sensitivity by hyperinsulinaemic euglucaemic clamp; minimal forearm vascular resistance (MFVR) by plethysmography; intima-media cross-sectional area of the common carotid arteries (IMA) by ultrasound; and LV mass, relative wall thickness (RWT), systolic function and diastolic filling by echocardiography after two weeks of placebo treatment. LV mass index correlated to IMA/height (r=0.36, P=0.001), serum insulin (r=-0.25, P<0.05), plasma glucose (r=-0.34, P<0.01), and showed a tendency towards a correlation to insulin sensitivity (r=0.21, P=0.051), but was unrelated to MFVR. Deceleration time of early diastolic transmitral flow positively correlated to IMA/height (r=0.30, P<0.01). The ratio between early and atrial LV filling peak flow velocity negatively correlated to MFVR(men) (r=-0.30, P<0.05). Endocardial and midwall systolic LV function were not related to vascular hypertrophy, plasma glucose, serum insulin or insulin sensitivity. In conclusion, insulin resistance was not related to LV hypertrophy or reduced LV function. However, high thickness of the common carotid arteries was associated with LV hypertrophy and high deceleration time of early diastolic transmitral flow. High MFVR was associated with low ratio between early and atrial LV filling peak flow velocity. This may suggest that systemic vascular hypertrophy contributes to abnormal diastolic LV relaxation in patients with hypertension and electrocardiographic LV hypertrophy.

A blood pressure independent association between glomerular albumin leakage and electrocardiographic left ventricular hypertrophy. The LIFE Study. Losartan Intervention For Endpoint reduction

In the Losartan Intervention For Endpoint reduction (LIFE) study left ventricular (LV) hypertrophy was associated with increased urine albumin/creatinine ratio (UACR) at baseline. To evaluate whether this association was due only to parallel blood pressure (BP)-induced changes we re-examined the patients after 1 year of antihypertensive treatment to investigate whether changes in LV hypertrophy and UACR were related independently of changes in BP. In 7,142 hypertensive patients included in the LIFE study, we measured UACR, LV hypertrophy by electrocardiography, plasma glucose and BP after 2 weeks of placebo treatment and again after 1 year of antihypertensive treatment with either an atenolol or a losartan based regime. At baseline and still after 1 year of treatment logUACR (R = 0.28, P < 0.001) was still correlated to LV hypertrophy (beta = 0.05) assessed by ECG independently of systolic BP (beta = 0.16), plasma glucose (beta = 0.19) and age (beta = 0.08). Change in logUACR (R = 0.19, P < 0.001) during treatment was correlated to change in LV hypertrophy (beta = 0.10) independently of reduction in systolic BP (beta = 0.13) and change in plasma glucose (beta = 0.06). After 1 year of antihypertensive treatment UACR was still related to LV hypertrophy independently of systolic BP, and the reduction in UACR during that first year of treatment was related to regression of LV hypertrophy independently of reduction in systolic BP. This suggests that the relationship between LV hypertrophy and glomerular albumin leakage is not just due to parallel BP-induced changes. As glomerular albumin leakage may represent generalised vascular damage we hypothesise a vascular relationship between cardiac and glomerular damage.

Maximal exercise capacity is related to cardiovascular structure in patients with longstanding hypertension. A LIFE substudy. Losartan Intervention For Endpoint-Reduction in Hypertension

BACKGROUND

Cardiovascular hypertrophy and remodeling in patients with never-treated hypertension has been associated with impaired exercise capacity, but whether this relationship remains in patients with longstanding hypertension and target organ damage is less elucidated.

METHODS

In 43 unmedicated patients with essential hypertension and electrocardiographic left ventricular (LV) hypertrophy, we measured maximal workload and oxygen reserve by bicycle test, 24-h ambulatory blood pressure (BP), LV mass index by magnetic resonance imaging (LVMI(MRI), n = 31), LVMI(echo) and systemic vascular compliance by echocardiography, minimal forearm vascular resistance (MFVR) by plethysmography, and intima media thickness and distensibility in the common carotid arteries by ultrasound.

RESULTS

The patients did not achieve the maximal workload as predicted by age, gender and body composition (146[129-163] v 162[146-179] Watt, P = .01). This impaired exercise capacity, calculated as the ratio between achieved and predicted maximal workload, was in simple regression analyses related to lower distensibility of the common carotid artery (r = 0.38, P = .01) and lower oxygen reserve (r = 0.68, P < .001). In multiple regression analyses, lower oxygen reserve was related to higher LVMI(MRI) (beta = -0.44), lower systemic vascular compliance (beta = -0.36), and higher MFVR (beta = -0.52) (adjusted R2 = 0.53, P < .001).

CONCLUSIONS

Patients with longstanding hypertension and target organ damage cannot achieve the predicted maximal workload. This impaired exercise capacity was associated with lower common carotid distensibility and lower oxygen reserve. The latter was independently related to LV hypertrophy, low systemic vascular compliance and peripheral vascular remodeling, suggesting that cardiovascular hypertrophy and remodeling may reduce exercise capacity by itself.