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Publications and source records attributed to R B Devereux.
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AIMS/HYPOTHESIS: We aimed to: (1) define the prevalence of type 2 diabetes and IFG in Eskimos in Norton Sound, Alaska; (2) determine correlates of prevalent diabetes in this population; and (3) compare the prevalence of diabetes in the Genetics of Coronary Artery Disease in Alaska Natives (GOCADAN) Study with other samples of Eskimos, Inuit, American Indians and US blacks, whites and Mexican Americans. METHODS: The GOCADAN Study enrolled 1,214 participants >or=18 years who were members of extended pedigrees from the Norton Sound region of Alaska. Diagnosed type 2 diabetes was based on reported use of insulin or hypoglycaemic medications and a medication inventory. Fasting glucose measurements were obtained to ascertain IFG status and undiagnosed diabetes according to American Diabetes Association (ADA) criteria. OGTTs were performed to ascertain diabetes according to the World Health Organization (WHO) definition. We used logistic regression analysis to model factors that were significantly associated with odds of prevalent ADA diabetes. RESULTS: The prevalences of ADA diabetes and IFG were 3.8% (5.0% of women; 2.2% of men) and 15.6% (13.9% of women; 17.7% of men), respectively. In the subset of 787 participants who took the OGTT, the prevalences of ADA and WHO diabetes were 5.1 and 6.9%, respectively. The adjusted odds of ADA diabetes was 2.8 times higher in participants meeting Adult Treatment Panel III criteria for abdominal obesity than in those who did not. The statistically significant sex-related difference in diabetes prevalence did not persist in multivariable analyses. CONCLUSIONS/INTERPRETATION: Alaska Eskimos have a low prevalence of type 2 diabetes. The high prevalence of IFG indicates that diabetes may become increasingly problematic in this population. Abdominal obesity in women may help explain why diabetes prevalence differs according to sex.
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.
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.
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.
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.
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.
The Losartan Intervention for Endpoint reduction in hypertension (LIFE) study was designed to compare losartan- vs atenolol-based antihypertensive treatment on cardiovascular morbidity and mortality in a population of 9193 hypertensive patients with left ventricular hypertrophy (LVH). In LIFE, the losartan-based treatment further reduced the primary composite end point (cardiovascular death, myocardial infarction, or stroke) by 13% (risk reduction (RR) 0.87, 95% confidence interval (CI) 0.77-0.98, P=0.021). The further reduction in stroke with losartan (RR 0.75, 95% CI 0.63-0.89, P=0.001) was the major contributing factor to the reduction in the primary end point. Our objective was to project the reduction in stroke observed with a losartan- vs an atenolol-based antihypertensive treatment regimen in the LIFE study to the European Union (EU) population. The number of stroke events averted was estimated by identifying the number of persons in the EU expected to meet the LIFE inclusion criteria, and multiplying this figure by the cumulative incidence risk difference in stroke from LIFE at 5.5 years. The age- and gender-specific prevalence of hypertension, electrocardiographically (ECG)-diagnosed LVH among those with hypertension (inclusion criteria), and heart failure among those with LVH and hypertension (exclusion criteria) were applied to the EU census estimates. We conservatively projected that an estimated 7.8 million individuals aged 55-80 years in the EU are affected by hypertension and ECG-diagnosed LVH. Use of a losartan-based antihypertensive treatment in this population is projected to prevent approximately 125 000 first strokes over a 5.5-year period. A population-wide prevention strategy of using losartan in patients with LVH and hypertension has the potential to have a major public health impact by reducing the morbidity and mortality of stroke in the EU.
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.
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.
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.
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.
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.
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.
The Losartan Intervention For End point reduction in hypertension (LIFE) study showed superiority of losartan over atenolol for reduction of composite risk of cardiovascular death, stroke, and myocardial infarction in hypertensives with left ventricular hypertrophy. We compared hazard ratios (HR) in 4287 and 685 participants who reported intakes of 1-7 and >8 drinks/week at baseline, respectively, with those in 4216 abstainers, adjusting for gender, age, smoking, exercise, and race. Within categories, clinical baseline characteristics, numbers randomized to losartan and atenolol, and blood pressure (BP) lowering were similar on the drug regimens. Overall BP control (<140/90 mmHg) at end of follow-up was similar in the categories. Composite end point rate was lower with 1-7 (24/1000 years; HR 0.87, P<0.05) and >8 drinks/week (26/1000 years; HR 0.80, NS) than in abstainers (27/1000 years). Myocardial infarction risk was reduced in both drinking categories (HR 0.76, P<0.05 and HR 0.29, P<0.001, respectively), while stroke risk tended to increase with >8 drinks/week (HR 1.21, NS). Composite risk was significantly reduced with losartan compared to atenolol only in abstainers (HR 0.81 95% confidence interval, CI (0.68, 0.96), P<0.05), while benefits for stroke risk reduction were similar among participants consuming 1-7 drinks/week (HR 0.73, P<0.05) and abstainers (HR 0.72, P<0.01). Despite different treatment benefits, alcohol-treatment interactions were nonsignificant. In conclusion, moderate alcohol consumption does not change the marked stroke risk reduction with losartan compared to atenolol in high-risk hypertensives. Alcohol reduces the risk of myocardial infarction, while the risk of stroke tends to increase with high intake.
BACKGROUND AND AIMS: To investigate whether insulin-resistance influences echocardiographic markers of preclinical disease, independent of significant confounders. METHODS AND RESULTS: We examined 1,471 (59 +/- 8 years) non-diabetic individuals (WHO criteria) with available echocardiograms from the Strong Heart Study cohort. Among them, 530 subjects had arterial hypertension (62% on medications), 152 had impaired glucose tolerance (GT) and 460 were normotensive, non-obese with normal GT. Insulin resistance was estimated by the Homeostasis Model Assessment (HOMA). LV mass, systolic function measured at the endocardium and the midwall (also correcting for circumferential wall stress) and arterial compliance (stroke volume/pulse pressure as a percent of predicted from body weight, age and heart rate [delta %SV/PP]) were measured by echocardiography, as prognostically validated markers of preclinical disease. HOMA-index was related positively to body mass index (BMI), waist/hip ratio (WHR), blood pressure, left ventricular (LV) mass, and negatively to arterial compliance (all p < 0.005) in the whole population, as well as in separate normotensive or hypertensive groups. In multiple regression models, relation of HOMA-index with the markers of risk was adjusted for age, sex, WHR, body mass index, presence of hypertension and number of antihypertensive medications. In this analysis, neither LV mass nor indices of systolic function were independently related to HOMA-index. In contrast, HOMA-index maintained a significant negative association with delta %SV/PP, independent of demographics, hypertension, treatment and body fat distribution. Also, HOMA-index maintained an independent relation with LV mass, when WHR and BMI were not included in the regression model. CONCLUSIONS: After accounting for relevant biological covariates, including body mass and fat distribution, insulin-resistance measured by HOMA is not an independent correlate of LV mass and function, but negatively influences arterial compliance.
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.
Active reduction of left ventricular chamber size during systole is the final effect of complex interaction mechanisms involving layers of differently oriented myocardial fibres, the shortening of which is less than the one measured as shortening of the left ventricular diameter at the level of the endocardium. This biological phenomenon is particularly evident in conditions such as arterial hypertension in which left ventricular geometry is altered. Due to the double effect of contraction on both the longitudinal (shortening) and transverse (thickening) axes of the myocardial fibres, the shortening of single myocardial fibres is amplified at the level of the endocardium and this amplification is a function of wall thickness. Increased wall thickness can enhance at the endocardial level the effect of myocardial fibres with reduced shortening, allowing preservation of ejection fraction despite depressed midwall shortening, through a 'contractile gradient' proceeding from epicardium to endocardium. This is detectable using tagged MRI or even quantitative echocardiography. This discrepancy between chamber and wall mechanics, seen in arterial hypertension and in other clinical conditions characterized by alteration of left ventricular geometry, is at the basis of the better prediction of cardiovascular risk in hypertensive patients by measures of left ventricular wall mechanics than by measures of left ventricular chamber function.