Left ventricular hypertrophy and impaired diastolic filling in essential hypertension. Diastolic mechanisms for systolic dysfunction during exercise

Stress echocardiography in heart failure patients: additive value and caveats

Heart failure (HF) is a clinical syndrome characterized by well-defined signs and symptoms due to structural and/or myocardial functional impairment, resulting in raised intracardiac pressures and/or inadequate cardiac stroke volume at rest or during exercise. This could derive from direct ischemic myocardial injury or other chronic pathological conditions, including valvular heart disease (VHD) and primary myocardial disease. Early identification of HF etiology is essential for accurate diagnosis and initiation of early and appropriate treatment. Thus, the presence of accurate means for early diagnosis of HF symptoms or subclinical phases is fundamental, among which echocardiography being the first line diagnostic investigation. Echocardiography could be performed at rest, to identify overt structural and functional abnormalities or during physical or pharmacological stress, in order to elicit subclinical myocardial function impairment e.g. wall motion abnormalities and raised ventricular filling pressures. Beyond diagnosis of ischemic heart disease, stress echocardiography (SE) has recently shown its unique value for the evaluation of diastolic heart failure, VHD, non-ischemic cardiomyopathies and pulmonary hypertension, with recommendations from international societies in several clinical settings. All these features make SE an important additional tool, not only for diagnostic assessment, but also for prognostic stratification and therapeutic management of patients with HF. In this review, the unique value of SE in the evaluation of HF patients will be described, with the objective to provide an overview of the validated methods for each setting, particularly for HF management.

Sex differences in the diagnostic algorithm of screening for heart failure by symptoms and NT-proBNP in patients with type 2 diabetes

OBJECTIVES

This study aimed to assess the guideline recommended diagnostic tools NT-proBNP and NYHA classification, with a focus on sex-specific differences.

BACKGROUND

Patients with Type 2 Diabetes (T2D) face a heart failure (HF) risk up to four times higher than those without T2D, particularly affecting women more than twice as much as men. Despite distinct pathophysiological differences between men and women, there are currently no sex-specific recommendations for the diagnostic algorithm of HF in diabetic patients.

METHODS

A total of 2083 patients with T2D were enrolled, and the primary endpoint was heart failure during hospitalization within a 5-year timeframe. The secondary endpoint was all-cause death.

RESULTS

In female patients, frequency of HF diagnosis prior to or during hospitalization and mortality did not differ significantly between NYHA II and III, in contrast to male patients. Additionally, there was no notable difference in mean NT-proBNP levels between NYHA stage II and III only in female patients. The multivariable regression analysis highlighted NYHA classification not to be a predictor of NT-proBNP levels in female but solely in male patients. On multivariable Cox regression NYHA score was also no significant risk factor for occurence of HF in female patients. Furthermore, there was no significant disparity in mortality between men with NT-proBNP levels between 125 and 400 pg/ml and those below 125 pg/ml, whereas in women mortality was significantly higher in the group with NT-proBNP levels between 125 and 400 pg/ml than below 125 pg/ml.

CONCLUSION

These findings suggest that NYHA classification may not be the most suitable tool for assessing the diagnosis of HF in female patients with T2D. Moreover, the need for consideration of a more symptom-independent screening for HF in female patients with T2D and re-evaluation of current guidelines especially regarding sex-specific aspects is highlighted.

Exercise-induced changes in left ventricular strain are affected by interleukin-6 activity: An exploratory analysis of a randomised-controlled trial in humans with abdominal obesity

Whilst the exercise-induced myokine interleukin-6 (IL-6) plays a beneficial role in cardiac structural adaptations, its influence on exercise-induced functional cardiac outcomes remains unknown. We hypothesised that IL-6 activity is required for exercise-induced improvements in left ventricular global longitudinal strain (LV GLS). In an exploratory study 52 individuals with abdominal obesity were randomised to 12 weeks' high-intensity exercise or no exercise in combination with IL-6 receptor inhibition (IL-6i) or placebo. LV strain and volume measurements were assessed by cardiac magnetic resonance. Exercise improved LV GLS by -5.4% [95% CI: -9.1% to -1.6%] (P = 0.007). Comparing the change from baseline in LV GLS in the exercise + placebo group (-4.8% [95% CI: -7.4% to -2.2%]; P < 0.0004) to the exercise + IL-6i group (-1.1% [95% CI: -3.8% to 1.6%]; P = 0.42), the exercise + placebo group changed -3.7% [95% CI: -7.4% to -0.02%] (P = 0.049) more than the exercise + IL6i group. However, the interaction effect between exercise and IL-6i was insignificant (4.5% [95% CI: -0.8% to 9.9%]; P = 0.09). Similarly, the exercise + placebo group improved LV global circumferential strain by -3.1% [95% CI: -6.0% to -0.1%] (P = 0.04) more compared to the exercise + IL-6i group, yet we found an insignificant interaction between exercise and IL-6i (4.2% [95% CI: -1.8% to 10.3%]; P = 0.16). There was no effect of IL-6i on exercise-induced changes to volume rates. This study underscores the importance of IL-6 in improving LV GLS in individuals with abdominal obesity suggesting a role for IL-6 in cardiac functional exercise adaptations.

Study the relationship between left atrial (LA) volume and left ventricular (LV) diastolic dysfunction and LV hypertrophy: Correlate LA volume with cardiovascular risk factors

Heart failure (HF) with normal ejection fraction - the isolated diastolic heart failure, depicts increasing prevalence and health care burden in recent times. Having less mortality rate compared to systolic heart failure but high morbidity, it is evolving as a major cardiac concern. With increasing clinical use of Left atrial volume (LAV) quantitation in clinical settings, LAV has emerged as an important independent predictor of cardiovascular outcome in HF with normal ejection fraction. This article is intended to review the diastolic and systolic heart failure, their association with left atrial volume, in depth study of Left atrial function dynamics with determinants of various functional and structural changes.

Serum aldosterone effect on left ventricular structure and diastolic function in essential hypertension

Aldosterone has hypertrophic and profibrotic effects on the heart. This study aims to determine the relationship between serum aldosterone concentration (SAC) and aldosterone-to-renin ratio (ARR) with left ventricular (LV) geometry and diastolic function in essential hypertension (EH). We investigated 213 EH patients (50.3 ± 12.6 years; 57.7% male). SAC, ARR measurements, and echocardiographic analysis were performed for participants. Overall, stepwise multiple regression analysis showed significant associations between SAC and interventricular septum, LV posterior wall thickness, LV amass, LV mass index, e' velocity, a' velocity, and E/e' ratio after adjustment of potentially confounding covariates. When patients were divided into three SAC tertiles, multivariate-adjusted analysis of covariance (ANCOVA) demonstrated a significant increase in LV mass (P ˂ 0.001), LV mass index (P ˂ 0.001), relative wall thickness (P = 0.003), interventricular septum (P = 0.001), LV posterior wall thickness (P = 0.001) and E/e' ratio (P ˂ 0.001), but a decrease in e' velocity (P = 0.002) from the first to third tertile of SAC. In logistic regression analysis, increased SAC was independently associated with concentric LV hypertrophy [OR: 1.21, 95% CI: 1.11-1.33, P ˂ 0.001]. No significant associations were found between ARR and echocardiographic parameters of LV structure or diastolic function. In conclusion, SAC, but not ARR, is independently associated with echocardiographic indices of LV structure and diastolic function and is also related to concentric LV hypertrophy. Our findings suggest that aldosterone's pro-hypertrophic and myocardial fibrosis effects contribute to alterations in LV structure and diastolic function in EH beyond blood pressure.

Subclinical HMOD in Hypertension: Left Ventricular Diastolic Dysfunction

Arterial hypertension represents an important risk factor for the development of cardiac, vascular and renal events, predisposing to heart failure, acute coronary syndromes, peripheral artery disease, stroke, and chronic renal disease. Arterial hypertension leads to the development of subclinical hypertension mediated organ damage (HMOD) which has prognostic relevance and may influence the choice of treatment options. Alterations of cardiac structure and function represent the more widely assessed form of HMOD. This manuscript will focus on the diagnostic opportunities, prognostic significance and treatment of diastolic dysfunction alterations.

Left atrial dysfunction as the major driver of heart failure with preserved ejection fraction syndrome

Left atrial (LA) dysfunction seems to play a central role in the pathophysiology of heart failure with preserved ejection fraction (HFpEF), is associated with disease severity and poor outcomes and potentially impacts management. Identifying LA myopathy can help guide tailored therapy for HFpEF. Echocardiography allows the accurate measurement of atrial size and function, where LA strain appears to be a sensitive measure of intrinsic LA myopathy. Several therapies and devices that decompress of left atrium are being tested for HFpEF. Further investigation is required to understand the specific atrial effects of statins, mineralocorticoid receptor antagonists, and other therapies.

Left atrial strain predicts cardiovascular response to exercise in young adults with suboptimal blood pressure

AIMS

To investigate the left ventricular response to exercise in young adults with hypertension, and identify whether this response can be predicted from changes in left atrial function at rest.

METHODS

A total of 127 adults aged 18-40 years who completed clinical blood pressure assessment and echocardiography phenotyping at rest and during cardiopulmonary exercise testing, were included. Measurements were compared between participants with suboptimal blood pressure ≥120/80mm Hg (n = 68) and optimal blood pressure <120/80mm Hg (n = 59). Left ventricular systolic function during exercise was obtained from an apical four chamber view, while resting left atrial function was assessed from apical four and two chamber views.

RESULTS

Participants with suboptimal blood pressure had higher left ventricular mass (p = 0.031) and reduced mitral E velocity (p = 0.02) at rest but no other cardiac differences. During exercise, their rise in left ventricular ejection fraction was reduced (p = 0.001) and they had higher left ventricular end diastolic and systolic volumes (p = 0.001 and p = 0.001, respectively). Resting cardiac size predicted left ventricular volumes during exercise but only left atrial booster pump function predicted the left ventricular ejection fraction response ( β = .29, p = 0.011). This association persisted after adjustment for age, sex, body mass index, and mean arterial pressure.

CONCLUSION

Young adults with suboptimal blood pressure have a reduced left ventricular systolic response to exercise, which can be predicted by their left atrial booster pump function at rest. Echocardiographic measures of left atrial function may provide an early marker of functionally relevant, subclinical, cardiac remodelling in young adults with hypertension.

Sex Differences in New York Heart Association Functional Classification and Survival in Acute Heart Failure Patients With Preserved or Reduced Ejection Fraction

BACKGROUND

The aim of this study was to evaluate the influence of sex on the relationship between the New York Heart Association (NYHA) functional classification and survival in acute decompensated heart failure (HF) patients with preserved or reduced ejection fraction (EF).

METHODS

Of 4842 patients enrolled in the Acute Decompensated Heart Failure Syndromes (ATTEND) registry, 4717 (2730 men and 1987 women) were investigated to assess the association of sex, NYHA functional class, and preserved or reduced EF with all-cause death. Men and women were divided into 6 groups based on left ventricular EF (preserved or reduced) and NYHA functional class (II, III, or IV) at admission.

RESULTS

Among both sexes with preserved EF, multivariable analysis confirmed that NYHA functional class IV was associated with a significantly higher risk of all-cause death than NYHA functional class II. Similarly, in women with reduced EF, NYHA functional class IV was a significant predictor of all-cause death compared with class II. However, in men with reduced EF, the adjusted risk of all-cause death was similar for those in NYHA functional classes II, III, and IV. Furthermore, the interaction between sex and NYHA functional classes II to IV was statistically significant for all-cause death in reduced EF patients (P for interaction = 0.037), but not in preserved EF patients (P for interaction = 0.711).

CONCLUSIONS

NYHA functional class IV was a significant predictor of all-cause death in both sexes with preserved EF, whereas NYHA functional class IV was a significant predictor of all-cause death in women, but not in men, with reduced EF.

Myocardial performance index in hypertensive disorders of pregnancy: The relationship between blood pressures and angiogenic factors

OBJECTIVE

To study the association between cardiac function measured by myocardial performance index (MPI), blood pressures and angiogenic factors measured at the time of echocardiography in patients with and without hypertensive disorders of pregnancy (HDP).

METHODS

We prospectively studied 189 pregnant women and evaluated whether changes in cardiac function observed on echocardiography were correlated with higher blood pressures and whether higher blood pressures were associated with antiangiogenic proteins (soluble fms-like tyrosine kinase, sFlt1; soluble endoglin, sEng). Comprehensive echocardiograms, including measurement of MPI, were performed on all patients. sFlt1 and sEng levels were measured using enzyme-linked immunosorbent assay.

RESULTS

Overall, 189 patients were divided into tertiles based on mean arterial pressure (MAP). The MPI was worst in tertile 3 (0.50 ± 0.15) compared to tertile 1 (0.42 ± 0.10), p = 0.0004. sFlt1 (pg/ml) and sEng (ng/ml) were highest in tertile 3 compared to tertile 1: 15055.37 vs. 1623.01 and 33.06 vs. 8.15, respectively, with p-value <0.001. In crude multivariate regression analysis, MAP was positively correlated with MPI (r = 0.32, p < 0.001), GLS (r = 0.54, p < 0.001), sFlt1 (r = 0.60, p < 0.001) and sEng (r = 0.61, p < 0.001). After adjustment for confounders, these relationships persisted between MAP and MPI (r = 0.31, p = 0.0003), GLS (r = 0.46, p < 0.001), sFlt1 (r = 0.56, p < 0.001) and sEng (r = 0.58, p < 0.001).

CONCLUSION

Mean arterial pressure correlates with worsening cardiac function as measured by MPI and serum levels of angiogenic factors. Further studies are needed to evaluate whether a reduction in blood pressure will reverse changes in MPI or reduce levels of angiogenic proteins seen among women with HDP.

Relationship of exercise capacity and left ventricular dimensions in patients with a normal ejection fraction. An exploratory study

OBJECTIVES

Extreme endurance exercise is known to be associated with an enlargement of the left ventricular (LV) chamber, whereas inactivity results in inverse changes. It is unknown if these dimensional relationships exist in patients.

METHODS

We analyzed the relationship of exercise capacity and LV dimension in a cohort of sequential patients with a normal ejection fraction undergoing stress echocardiography. In a total of 137 studies the following questions were addressed: (a) is there a difference in LV dimensions of patients with an excellent exercise capacity versus patients with a poor exercise capacity, (b) how is LV dimension and exercise capacity affected by LV wall thickness and (c) how do LV dimensions of patients who are unable to walk on a treadmill compare to the above groups.

RESULTS

Patients with a poor exercise capacity or who are unable to physically exercise have a 34 percent smaller LV cavity size when compared to patients with an excellent exercise capacity (p<0.001). This reduction in LV chamber size is associated with concentric LV hypertrophy and a reciprocal increase in resting heart rate. In addition, cardiac output reserve is further blunted by chronotropic incompetence and a tachycardia-induced LV volume reduction. In conclusion the relationship of exercise capacity and cardiac dimensions described in extreme athletes also applies to patients. Our exploratory analysis suggests that patients who cannot sufficiently exercise have small LV cavities.

Early diastolic functional abnormalities in normotensive offspring of Nigerian hypertensives

Background

Some studies have suggested that diastolic dysfunction precedes the clinical manifestation of hypertension. Whether changes in cardiac structure and function predate the clinical manifestation of hypertension later in life is now being investigated. The aim of this study was to assess the differences in cardiac structure and function between the offspring of hypertensive and normotensive parents.

Methods

Eighty normotensive offspring of hypertensive parents (OHyp) (41 females and 39 males) and 62 normotensive offspring of normotensive parents (ONorm) (31 males and 31 females) were recruited for echocardiography.

Results

The mean age was 25.0 (5.31) and 24.3 (3.60) years in the OHyp and ONorm participants, respectively (p = 0.369). Other baseline parameters were comparable between the two groups. Septal wall thickness in systole was higher in the OHyp than the ONorm subjects [1.3 (0.35) vs 1.1 (0.25), p = 0.0173]. Indexed left ventricular mass [28.1 (7.33) vs 27.5 (7.23), p = 0.631] and relative wall thickness [(0.3 (0.10) vs 0.3 (0.90), p = 0.280] were similar in the two groups. The offspring of hypertensives had lower deceleration time [149.9 (38.89) vs 169.0 (50.08) ms, p = 0.012], prolonged duration of pulmonary A reverse flow [113.5 (70.69) vs 81.7 (38.31) ms, p = 0.024], increased myocardial isovolumic relaxation time [173.4 (47.98) vs 156.1 (46.74) ms, p = 0.033] and a lower myocardial Em [0.2 (0.05) vs 0.3 (1.38), p = 0.037] and myocardial Em/Am ratio [1.6 (0.01) vs 2.1 (0.01), p = 0.019] than the offspring of normotensives.

Conclusion

This study showed that offspring of OHyp subjects had early diastolic functional abnormalities when compared with offspring of ONorm participants. Longitudinal studies are needed to determine the implications of this finding in this African population.

Selective improvement in renal function preserved remote myocardial microvascular integrity and architecture in experimental renovascular disease

AIM

Atherosclerotic renovascular disease (ARVD) may impair renal function and increase cardiovascular morbidity and mortality, but the mechanism by which ARVD impacts cardiovascular function is unclear. We tested the hypothesis that preservation of renal function can reverse cardiac dysfunction in ARVD.

METHODS AND RESULTS

Endothelial progenitor cells (EPC) were injected intra-renally (ARVD+EPC) after 6 weeks of swine ARVD (concurrent hypercholesterolemia and renovascular hypertension), and single-kidney function and myocardial blood-flow and microvascular permeability (MP) responses to adenosine were assessed using CT 4 weeks later. Myocardial microvascular density was evaluated by micro-CT. Inflammation and oxidative-stress were assessed in kidney venous and systemic blood samples. Normal and untreated ARVD pigs served as controls. Blood pressure was similarly increased in ARVD and ARVD+EPC. Compared to normal, ARVD showed lower glomerular filtration rate, elevated renal vein and systemic oxidized LDL (ox-LDL), aldosterone, uric acid, isoprostanes, transforming growth factor (TGF)-β, and interleukine-6. Renal vein ox-LDL and TGF-β showed a positive gradient across the stenotic kidney, indicating increased renal oxidative stress and fibrogenic activity. Furthermore, ARVD impaired myocardial blood-flow and MP response to adenosine, decreased microvascular density, and induced myocardial fibrosis. Improvement of renal function in ARVD+EPC decreased systemic aldosterone, inflammation, and oxidative stress, and improved myocardial microvascular integrity and density.

CONCLUSION

Selective improvement in renal function, which reduced renal and systemic oxidative stress and inflammation, preserved remote myocardial microvascular function and architecture, despite enduring hypertension. These findings underscore functionally important cardiorenal crosstalk possibly mediated by renal injury signals.

The use of exercise echocardiography in the evaluation of mitral regurgitation

Mitral regurgitation (MR) is the second most common valvular disease in western countries after aortic stenosis. Optimal management of patients with MR depends on the etiology of the regurgitation and is based predominantly on left ventricular function and functional status. Recent outcome studies report high risk subsets of asymptomatic patients with MR, and practice guidelines underscore the importance of a well-established estimation of exercise tolerance and recommend exercise testing to objectively assess functional status and hemodynamic factors.

Measurements of changes in left ventricular volume, strain, and twist during isovolumic relaxation using MRI

Left ventricular (LV) active relaxation begins before aortic valve closure and is largely completed during isovolumic relaxation (IVR), before mitral valve opening. During IVR, despite closed mitral and aortic valves, indirect assessments of LV volume have suggested volume increases during this period. The aim of this study is to measure LV volume throughout IVR and to determine the sources of any volume changes. For 10 healthy individuals (26.0 ± 3.8 yr), magnetic resonance imaging was used to measure time courses of LV volume, principal myocardial strains (circumferential, longitudinal, radial), and LV twist. Mitral leaflet motion was observed using echocardiography. During IVR, LV volume measurements showed an apparent increase of 4.6 ± 1.5 ml (5.0 ± 2.0% of the early filling volume change), the LV untwisted by 4.5 ± 1.9° (36.6 ± 18.0% of peak systolic twist), and changes in circumferential, longitudinal, and radial strains were +0.87 ± 0.64%, +0.93 ± 0.57%, and −1.46 ± 1.66% (4.2 ± 3.3%, 5.9 ± 3.3%, and 5.3 ± 7.5% of peak systolic strains), respectively. The apparent changes in volume correlated ( P < 0.01) with changes in circumferential, longitudinal, and radial strains ( r = 0.86, 0.69, and −0.37, respectively) and untwisting ( r = 0.83). The closed mitral valve leaflets were observed to descend into the LV throughout IVR in all subjects in apical four- and three-chamber and parasternal long-axis views by 6.0 ± 3.3, 5.1 ± 2.4, and 2.1 ± 5.0 mm, respectively. In conclusion, LV relaxation during IVR is associated with changes in principal strains and untwisting, which are all correlated with an apparent increase in LV volume. Since closed mitral and aortic valves ensure true isovolumic conditions, the apparent volume change likely reflects expansion of the LV myocardium and the inward bowing of the closed mitral leaflets toward the LV interior.

Effect of changes in left ventricular diastolic function during exercise on exercise tolerance assessed by exercise-stress tissue Doppler echocardiography

Cardiac function during exercise is assumed to be important in determining exercise tolerance. The aims of this study were to evaluate changes in left ventricular diastolic function (LVDF) during exercise and its effect on exercise tolerance assessed by a noninvasive method, exercise-stress tissue Doppler echocardiography. Twenty-six men with sinus rhythm (controls, hypertension, and cardiomyopathy) underwent cardiopulmonary exercise testing. To assess LVDF during exercise, exercise-stress Doppler echocardiography was performed with a constant workload at rest, and at 50%, 100%, and 120% of anaerobic threshold (AT). Doppler variables related to LVDF increased significantly as the workload increased (P < 0.05). Resting E'correlated significantly with AT (r = 0.424, P = 0.0308) and peak VO(2) (r = 0.471, P = 0.0152). However, the difference in E'between rest and 120% AT (DeltaE') was closely correlated with AT (r = 0.744, P < 0.0001) and peak VO(2) (r = 0.748, P < 0.0001). Moreover, DeltaE'was correlated independently with AT (P = 0.0321) and peak VO(2) (P = 0.0192) by multiple regression analysis. These results suggest that the ability to increase LVDF during exercise is an important factor in determining exercise tolerance.

Clinical impact of left ventricular hypertrophy and implications for regression

Left ventricular hypertrophy (LVH) is an independent risk factor and predictor of cardiovascular (CV) events and all-cause mortality. Patients with LVH are at increased risk for stroke, congestive heart failure, coronary heart disease, and sudden cardiac death. Left ventricular hypertrophy represents both a manifestation of the effects of hypertension and other CV risk factors over time as well as an intrinsic condition causing pathologic changes in the CV structure and function. We review the risk factors for LVH and its consequences, concentric remodeling, and its prognostic significance, clinical benefits and supporting evidence for LVH regression, and its implications for management. We conclude our review summarizing the various pharmacological and nonpharmacological therapeutic options approved for the treatment of hypertension and LVH regression and the supporting clinical trial data for these therapeutic strategies.

Increased atrial contribution to left ventricular filling compensates for impaired early filling during exercise in heart failure with preserved ejection fraction

BACKGROUND

The role of left atrial (LA) function on exercise remains poorly understood in heart failure with preserved ejection fraction (HfpEF) despite its key role in optimizing left ventricular (LV) diastolic function. We used resting and exercise radionuclide ventriculography to investigate the role of LA function in the pathophysiology of HfpEF.

METHODS AND RESULTS

A total of 25 patients with HfpEF and 15 age- and gender-matched controls were recruited. All subjects underwent resting echocardiogram, metabolic exercise testing to peak effort, and radionuclide ventriculography (at rest and exercise [to 35% of heart rate reserve]). At rest LA and LV function were similar in patients and controls. During exercise, HfpEF patients had lower left ventricular ejection fraction (69 +/- 9% vs. 73 +/- 10%, P < .05) and lower peak early filling rate (387 +/- 109 end-diastolic count/sec vs. 561 +/- 156 end-diastolic count/sec, P < .001). During exercise, the atrial contribution to LV filling was significantly higher in patients than controls (46 +/- 11% vs. 30 +/- 9%, P < .001). Atrial contribution to LV filling correlated negatively with peak early filling rate during exercise (r = -0.6, P < .001). Peak early filling rate correlated positively with peak oxygen consumption (r = 0.485, P = .004) and negatively with minute/carbon dioxide production (r = -0.423, P = .013).

CONCLUSION

Patients with HfpEF have increased atrial contribution to LV filling as a compensatory response to impaired early LV filling during cycle exercise.

Cardiac performance during exercise in hypertensive patients without ventricular hypertrophy

BACKGROUND

Reduced systolic reserve on effort may be present in subjects with hypertension but no evidence of hypertensive cardiomyopathy. We assessed the determinants of abnormal cardiac performance during exercise in hypertensive patients without left ventricular hypertrophy.

MATERIALS AND METHODS

Thirty-five newly diagnosed, never-treated-earlier hypertensive patients without definite indication for left ventricular hypertrophy at echocardiography underwent radionuclide ambulatory monitoring of left ventricular function at rest and during upright bicycle exercise testing.

RESULTS

The patients were classified into two groups according to their ejection fraction response to exercise. In 21 patients (group 1), the ejection fraction increased > or = 5% with exercise and in 14 patients (group 2), the ejection fraction either increased < 5% or decreased with exercise. Patients of group 1 had lower peak filling rate at rest and less augmentation in end-diastolic volume during exercise (both P < 0.01) when compared with patients of group 2. A significant relationship between the magnitude of change in ejection fraction with exercise and both peak filling rate at rest (r = 0.58, P < 0.01) and exercise-induced change in end-diastolic volume (r = 0.45, P < 0.01) was found.

CONCLUSIONS

In newly diagnosed, never-treated-earlier hypertensive subjects with no evidence of hypertensive cardiomyopathy, the cardiac response to exercise is dependent on adequate diastolic filling volume to maintain systolic performance.

Comparison of the echocardiographic and pulmonary function test findings in orderly treated and untreated essential hypertensive patients

OBJECTIVE

Although it has been well established that hypertension effects pulmonary functions negatively, the effect of regular antihypertensive therapy on pulmonary functions is not known. In this study, we aimed to compare the pulmonary function tests of the hypertensive patients taking regular antihypertensive therapy with those of the ones not taking any antihypertensive medicine, to document the differences in pulmonary functions of both hypertensive groups.

MATERIALS AND METHODS

Patients who had received antihypertensive treatment (Group I: 29 males, 24 females, mean age 42.3 +/- 8.2 years), and untreated cases (Group II: 28 males, 22 females, mean age 43.4 +/- 6.4 years) were included in the study. Patients with a history of coronary heart disease, respiratory diseases, smokers and those who were obese were excluded from the study.

RESULTS

Forced vital capacity (FVC) and forced expiratory volume at the first second (FEV1) levels were found significantly lower in Group II (p < 0.05). In echocardiographic evaluation, the mitral E/A ratio of Group II was lower than that of Group I (p < 0.05). Isovolumetric relaxation time and deceleration time was higher in Group II than in Group I (p < 0.05). There was a significant association between pulmonary function tests and impaired left ventricular diastolic parameters; especially, mitral E/A ratio was significantly associated with decreased FVC and FEV1 in Group II (respectively r = -0.695, p = 0.01 and r = -0.591, p = 0.03).

CONCLUSION

FVC and FEV1 levels in untreated hypertensive cases were lower than in those of treated hypertensive cases, and this may be caused by diastolic function rather than the systolic function. In the evaluation of dyspnea in hypertensive patients, it would be useful to examine respiratory function in addition to echocardiographic investigation.

Left ventricular function and exercise tolerance in patients with type II diabetes mellitus

BACKGROUND

Left ventricular (LV) preload changes may alter exercise tolerance (ET), probably lessening activation of the Maestrini-Starling mechanism. Reduced LV filling (pre-load) during the diastolic phase, usually impaired in diabetic patients, could affect ventricular function.

HYPOTHESIS

To evaluate the relationship between some echocardiographic LV function indices and ET, 24 patients (age 43-75 years, mean 54 +/- 13 years, Group A) with type II diabetes mellitus (DM), not suffering from other pathologies, and for whom the ergometric stress test (EST) resulted in an early interruption because of muscular fatigue and/or dyspnea, and 14 patients (age 38-70 years, mean 53 +/- 12 years, Group B) with type II DM and maximal ergometric stress test, used as control group, were studied.

METHODS

The EST was performed by increasing the load by 25 W every 2 min; its duration was used as an ET index and correlated with clinical parameters of LV function obtained with M-mode, two-dimensional, and Doppler echocardiography.

RESULTS

No patients in either Group A or Group B showed a high systolic blood pressure value at rest and/or an LV hypertrophy and/or an alteration of systolic functional indices. In neither group was there significant correlation between ET and duration of DM, basal heart rate, basal and max systolic blood pressure, and EF values. Linear regression analysis showed a significant correlation between Doppler parameters of the diastolic function and ET index in Group A, while there was no significant correlation in Group B.

CONCLUSION

From these data we can deduce that in absence of left systolic ventricular dysfunction the impairment of LV relaxation in DM can influence exercise tolerance, probably by limiting activation of the contractile reserve.

Cardiac performance during exercise in patients with Fabry's disease

BACKGROUND

Fatigability and dyspnoea on effort are present in many patients with Fabry's disease. We assessed the determinants of cardiac performance during exercise in patients with Fabry's disease and preserved left ventricular ejection fraction at rest.

MATERIALS AND METHODS

Sixteen patients with Fabry's disease and 16 control subjects underwent radionuclide angiography at rest and during exercise, tissue Doppler echocardiography and magnetic resonance imaging at rest.

RESULTS

The exercise-induced change in stroke volume was +25 +/- 14% in controls and +5.8 +/- 19% in patients with Fabry's disease (P < 0.001). In 10 patients (group 1), the stroke volume increased (+19 +/- 10%), and in 6 patients (group 2) it decreased (-16 +/- 9%) with exercise. Patients of group 2 were older, had worse renal function, higher left ventricular mass and impaired diastolic function compared to group 1. The abnormal stroke volume response to exercise in group 2 was associated with a decrease in end-diastolic volume (P < 0.001) and a lack of reduction of end-systolic volume (P < 0.01) compared with both controls and group 1. The ratio of peak early-diastolic velocity from mitral filling to peak early-diastolic mitral annulus velocity was the only independent predictor of exercise-induced change in stroke volume (B -0.44; SE 0.119; beta-0.70; P < 0.005).

CONCLUSIONS

The majority of patients with Fabry's disease were able to augment stroke volume during exercise by increasing end-diastolic volume, whereas patients with more advanced cardiac involvement may experience the inability to increase cardiac output by the Frank Starling mechanism.

Clinical significance of diastolic function as an indicator of myocardial ischemia assessed by 16-frame gated myocardial perfusion SPECT

OBJECTIVE

Studies have suggested that ischemia-induced diastolic dysfunction persists longer than systolic dysfunction. We examined whether global left ventricular (LV) diastolic function during stress testing assessed by 16-frame gated myocardial perfusion single-photon emission computed tomography (SPECT) is useful as an indicator of myocardial ischemia.

METHODS

Thirty-nine patients underwent 16-frame technetium-99m (Tc-99m) quantitative gated SPECT (QGS), including treadmill exercise testing for suspected ischemic heart disease. Diastolic parameters of the first-third filling fraction (1/3FF), and the peak filling rate (PFR) were calculated by a time-volume curve from the QGS data.

RESULTS

The patients were divided into four groups, namely, IS, NL, DN, and DD, on the basis of tracer accumulation and the LV ejection fraction (LVEF) at rest. In the IS group (reversible tracer uptake reduction suggesting ischemia; n=11), LVEF, 1/3FF, and PFR after stress were significantly lower than those at rest, whereas in the NL group (normal perfusion; n=10) and DN group (fixed tracer uptake reduction with normal systolic function; EF>or=60% at rest; n=10), LVEF, 1/3FF, and PFR after stress did not differ from those at rest. However, in the DD group (fixed tracer uptake reduction with cardiac dysfunction; EF<60%, average 47.1%; n=8), LVEF, 1/3FF, and PFR were significantly altered after stress.

CONCLUSIONS

Altered global LV diastolic function during stress assessed by 16-frame gated myocardial perfusion SPECT is useful for the detection of myocardial ischemia. However, similar findings are observed in patients with cardiac dysfunction but without detectable ischemia. Our findings do suggest that tests should be performed with caution to determine whether ischemia exists on the basis of altered global LV function after stress in patients with cardiac dysfunction.

Major weight loss prevents long-term left atrial enlargement in patients with morbid and extreme obesity

AIMS

To assess long-term changes in left atrial (LA) volume in patients with morbid obesity [body mass index (BMI) >or=35 kg/m(2) with co-morbidities] and extreme obesity (BMI >or=40 kg/m(2)), after surgically-induced weight loss (WL) after gastric bypass surgery.

METHODS AND RESULTS

We reviewed 57 patients who underwent gastric bypass surgery and had echocardiograms both before and after the operation. A control group was frequency-matched for BMI, sex, age, and for duration of follow-up. After a mean follow-up of 3.6 years, LA volume did not change significantly in patients who underwent bariatric surgery, but increased in the control group by 15 +/- 28 ml (P < 0.0001), and 0.1 +/- 0.2 ml (P < 0.0001) for height-indexed LA volume, with a difference between cases and controls that remained significant after adjusting for potential confounders (P = 0.01). In the study population as a whole, there was a positive correlation between change in body weight and change in LA volume (r = 0.22, P = 0.006) independent of clinical conditions associated with LA enlargement.

CONCLUSION

Change in body weight is associated with change in LA size independent of obesity-associated co-morbidities. Successful WL induced by bariatric surgery prevents the progressive increase in LA volume.

Dual-source CT with improved temporal resolution in assessment of left ventricular function: a pilot study

OBJECTIVE

Functional analysis using MDCT has been limited by insufficient temporal resolution. The aim of this study was to assess the performance of a dual-source CT system with improved temporal resolution in the determination of both volume- or time-dependent functional parameters and regional wall motion in comparison with cine MRI.

SUBJECTS AND METHODS

Twenty patients (15 of whom had previous myocardial infarction) were prospectively examined using dual-source CT. MRI was used as the standard of reference. Using the Simpson's method, ventricular volumes were determined for the whole of the cardiac cycle and results compared using Parson's correlation and Bland-Altman analysis. Regional wall motion was assessed on cine images and compared using weighted kappa statistics.

RESULTS

Dual-source CT revealed a strong correlation with cine MRI regarding the quantification of end-diastolic volume (r = 0.98), end-systolic volume (r = 0.99), stroke volume (r = 0.96), and ejection fraction (r = 0.95). Good correlation was obtained for peak ejection rate (r = 0.79) and peak filling rate (r = 0.84), whereas agreement proved only moderate for time-to-peak ejection rate (r = 0.68) or time-to-peak filling rate from end-systole (r = 0.64). The mean difference for ejection fraction was negligible (bias, 0.72%). Good agreement between both techniques was likewise found for regional wall motion (kappa = 0.88).

CONCLUSION

With the improvement of temporal resolution between 42 and 83 milliseconds, dual-source CT not only enables accurate assessment of global functional parameters, but it also allows for quantification of time-dependent variables and reliable evaluation of regional wall motion.

Cardiomyocyte-restricted restoration of nitric oxide synthase 3 attenuates left ventricular remodeling after chronic pressure overload

Although nitric oxide synthase (NOS)3 is implicated as an important modulator of left ventricular (LV) remodeling, its role in the cardiac response to chronic pressure overload is controversial. We examined whether selective restoration of NOS3 to the hearts of NOS3-deficient mice would modulate the LV remodeling response to transverse aortic constriction (TAC). LV structure and function were compared at baseline and after TAC in NOS3-deficient (NOS3−/−) mice and NOS3−/− mice carrying a transgene directing NOS3 expression specifically in cardiomyocytes (NOS3−/−TG mice). At baseline, echocardiographic assessment of LV dimensions and function, invasive hemodynamic measurements, LV mass, and myocyte width did not differ between the two genotypes. Four weeks after TAC, echocardiographic and hemodynamic indexes of LV systolic function indicated that contractile performance was better preserved in NOS3−/−TG mice than in NOS3−/− mice. Echocardiographic LV wall thickness and cardiomyocyte width were greater in NOS3−/− mice than in NOS3−/−TG mice. TAC-induced cardiac fibrosis did not differ between these genotypes. TAC increased cardiac superoxide generation in NOS3−/−TG but not NOS3−/− mice. The ratio of NOS3 dimers to monomers did not differ before and after TAC in NOS3−/−TG mice. Restoration of NOS3 to the heart of NOS3-deficient mice attenuates LV hypertrophy and dysfunction after TAC, suggesting that NOS3 protects against the adverse LV remodeling induced by prolonged pressure overload.

Associations of Gender and Etiology With Outcomes in Heart Failure With Systolic Dysfunction

OBJECTIVES

This study sought to explore the gender-related differences in etiology and outcomes in chronic heart failure (HF) patients from 5 randomized trials.

BACKGROUND

Each year, 550,000 new cases of HF are identified; however, there remain limited data on gender-related differences in etiology and outcomes among patients with HF with systolic dysfunction.

METHODS

We analyzed data from 8,791 men and 2,851 women randomized in 5 clinical trials (PRAISE [Prospective Randomized Amlodipine Survival Evaluation], PRAISE-2, MERIT-HF [Metoprolol Extended Release Randomized Intervention Trial in Heart Failure], VEST [Vesnarinone Trial], and PROMISE [Prospective Randomized Milrinone Survival Evaluation]) to explore gender-related differences in etiology (ischemic vs. nonischemic) and outcomes (all-cause mortality and death or all-cause hospitalization). Hazard ratios (HR), 95% confidence intervals (CIs), and Kaplan-Meier survival curves were generated by gender and etiology.

RESULTS

A total of 18% of ischemic and 31% of nonischemic patients were women. Irrespective of etiology, women were older, more ethnically diverse, and had higher systolic blood pressures, more diabetes, and severe HF symptoms, but less often smoked or had prior myocardial infarctions than men. Mean ejection fractions were similar between women (23.6%) and men (23.2%). The 1-year Kaplan-Meier survival estimates varied by gender and etiology (female nonischemics, HR 0.88 [95% CI 0.85 to 0.89]; female ischemics, HR 0.83 [95% CI 0.81 to 0.85]; male nonischemics, HR 0.84 [95% CI 0.83 to 0.85]; male ischemics, HR 0.79 [95% CI 0.78 to 0.81]). After adjustment, female gender (HR 0.77 [95% CI 0.69 to 0.85]) and nonischemic etiology (HR 0.80 [95% CI 0.72 to 0.89]) were associated with longer survival time. Time to death or hospitalization was longer among nonischemics (HR 0.83 [95% CI 0.78 to 0.89], p < 0.0001); however, female gender was not significantly associated with the composite outcome (HR 1.01 [95% CI 0.95 to 1.08]).

CONCLUSIONS

Our data clarify that outcomes differ by both gender and etiology among patients with HF with systolic dysfunction. Understanding these differences may lead to better management of HF patients and improved overall prognosis.

Role of Diastolic Dyssynchrony in the Delayed Relaxation Pattern of Left Ventricular Filling

We investigated the extent to which diastolic dyssynchrony contributes to the delayed relaxation pattern of left ventricular filling and limitation in exercise capacity. In 100 patients with diabetes, preserved left ventricular systolic function, normal filling pressure, and no coronary disease, we measured magnitude of early diastolic tissue lengthening (tissue velocity and strain rate) and diastolic dyssynchrony (SD in QRS to peak early diastolic tissue velocity interval across 4 basal myocardial segments). From transmitral flow patients were divided into those with normal filling (50 patients) and delayed relaxation (50 patients). Myocardial lengthening was reduced and SD in interval from QRS onset to peak early diastolic tissue velocity across all segments was higher in patients with delayed relaxation compared with control patients. Myocardial lengthening was the only predictor of delayed relaxation and correlation with exercise capacity was better for lengthening indices than SD in interval from QRS onset to peak early diastolic tissue velocity across all segments. Therefore, in this group a reduced rate of myocardial lengthening plays a more important role in delayed relaxation than diastolic dyssynchrony.

Modified TEI Index: A Promising Parameter in Essential Hypertension?

PURPOSE

Modified TEI index is pointed to be more effective in the evaluation of global cardiac functions compared to systolic and diastolic measurements alone. We planned to determine its applicability in hypertension and relation with left ventricular mass index (LVMI).

METHODS

We studied 48 patients with mild/moderate hypertension and normal coronary angiograms. In total 22 patients (12 men, 10 women, mean age: 55 +/- 6) with normal LVMI were studied in group I, 26 patients (12 men, 14 women, mean age: 57 +/- 7) with increased LVMI in group II, and 20 patients (10 men, 10 women, mean age: 53 +/- 7) with normal blood pressure as a control group. Standard 2D, Doppler, and mitral annulus pulse wave tissue Doppler were used for all measurements. Modified TEI index was calculated as diastolic time interval measured from end of Am wave to origin of Em (a') minus systolic Sm duration (b') divided by b(a'-b'/b').

RESULTS

Modified TEI index was significantly higher in both groups than normal group and in group II than in group I. (

CONTROL GROUP

0.33 +/- 0.05, group I: 0.51 +/- 0.17, group II: 0.68 +/- 0.16, P< 0.0001).

CONCLUSION

Modified TEI index, a marker of left ventricular systolic and diastolic functions, is impaired in hypertensives before hypertrophy develops and impairment is more prominent in hypertrophy. Therefore, (1) modified TEI index in hypertensives is a safe, feasible, and sensitive index for evaluation of global ventricular functions. (2) Evaluation of hypertensives with this index periodically may guide interventions directed toward saving systolic and diastolic functions. (3) Modified TEI index is gaining importance as a complementary parameter to standard Doppler or in cases where standard Doppler has its limitations.

Impact of left ventricular diastolic function on exercise capacity in patients with chronic mitral regurgitation: an exercise echocardiography study

BACKGROUND

Mitral regurgitation (MR) is known as one of the most frequent causes of heart failure and sudden death. In spite of increasing prevalence of MR, there have been no available data on cardiac determinants of exercise capacity in patients with chronic MR.

HYPOTHESIS

This study aimed to investigate cardiac determinants of exercise capacity in patients with chronic MR.

METHODS

We consecutively enrolled 32 patients (11 men, mean age: 44 +/- 14 years) who had greater than moderate MR with normal left ventricular (LV) systolic function (LV ejection fraction >50%). Conventional echocardiographic indices and parameters measured by Doppler tissue imaging at septal side of mitral annulus were obtained before exercise. Mitral regurgitation fraction, forward stroke volume, pulmonary venous flow velocities, and systolic pulmonary artery pressure (sPAP) were also obtained with standard methods.

RESULTS

Left ventricular ejection fraction was 61 +/- 6% and MR fraction was 48 +/- 13%. All patients finished a symptom-limited treadmill exercise test with a peak heart rate of >85% of predicted maximum heart rate. Mean exercise time was 9.95 +/- 2.17 min, corresponding to 11 +/- 2 metabolic equivalents. Among pre-exercise echocardiographic variables, only early diastolic mitral annulus velocity (E') and pulmonary venous reversal flow velocity (PVa) showed a significant correlation with exercise time (r = 0.44, p = 0.011, and r = -0.40, p = 0.040, respectively), which persisted after multivariate analysis (p = 0.011 and 0.038, respectively). Other parameters such as systolic mitral annulus velocity, resting and postexercise sPAP, forward stroke volume, LV size, LV ejection fraction, left atrial size, and regurgitant fraction showed no significant correlation.

CONCLUSIONS

Left ventricular diastolic function is an important determinant of exercise capacity in patients with chronic MR. Both E' and PVa, accepted surrogate estimates for LV diastolic function, may be useful for identifying patients with chronic MR and with poor exercise capacity.

Early Target Organ Damage and Its Reversibility: The Heart

Left ventricular hypertrophy (LVH) represents not only an adaptation to increased load, but also a risk factor and a marker of risk of cardiovascular diseases. It may be detected early in the development of the disease by electrocardiography or echocardiography. LVH is often associated to abnormalities of systolic and diastolic function, and its presence clearly predisposes not only to cardiac ischemia and to congestive heart failure, but also to a higher incidence of stroke. A large number of clinical and experimental studies have shown that long-term antihypertensive treatment may be associated with regression of LVH. Long-term antihypertensive treatment is associated with a progressive decrease of LV mass. Differences on reduction of LV mass using different classes of antihypertensive drugs for the same decrease of blood pressure are usually mild, although the effect on cardiac structure and tissue composition are probably not the same. In fact, not only the quantity of left ventricular mass, but also its quality (i.e., collagen content, contractile machinery) should be evaluated and improved by treatment. The incidence of cardiovascular events in hypertensive patients is clearly related to the value of LV mass achieved during treatment; in fact, a reduction in LVH by antihypertensive treatment is associated with improvement in outcome and with decrease of the risk of cardiovascular morbidity and mortality, even independently from changes of other risk factors, including blood pressure. In patients with LVH at baseline, the decrease of LV mass is associated with a number of pathophysiological changes such as 1) improved systolic performance at the midwall, 2) possible improvement of diastolic filling, 3) autonomic nervous system changes toward normalization, 4) possible reduction or ventricular arrhythmias and 5) coronary reserve improvement. All these changes might explain an improvement of clinical prognosis in hypertensive patients. Ongoing studies will more precisely assess the quantitative relation between development or regression of LV mass, improvement of systolic and diastolic function and incidence of cardiovascular events. At present time detection, prevention and reversal of LVH represent a major goal in the management of hypertensive patients.

Effect of acute blood pressure reduction on oxygen uptake kinetics at the onset of exercise in hypertensive patients

The aim of the present study was to investigate the adverse effects of hypertension on the cardiovascular system in daily activities and the effect of acute blood pressure reduction on oxygen (O(2)) uptake kinetics. Twenty hypertensive patients were included in the study group. Patients performed treadmill exercise tests (2.5 km/hour and 5 inclines) twice, before and after blood pressure reduction with sublingual captopril. In the control group, ten hypertensive patients underwent two tests one hour apart without blood pressure reduction brought about by drug therapy. The changes in O(2) kinetic values (O(2) deficit and mean response time [MRT]) between the two tests were investigated. In the study group, the O(2) deficit and MRT values measured during the first exercise testing were found to be 547 +/- 183 mL and 40 +/- 9 seconds, while those in the second exercise testing were 401 +/- 127 mL and 34 +/- 7 seconds, respectively. In the control group, the O(2) deficit and MRT values measured during the first exercise test were 491 +/- 217 mL and 42 +/- 16 seconds and 515 +/- 159 mL and 41 +/- 13 seconds in the second exercise test. The differences in O(2) deficit and MRT in the study group were considered to be statistically significant (P = 0.008 and P = 0.004, respectively). Based on our findings, there was a significant improvement in O(2) kinetic values with an acute reduction in blood pressure in hypertensive patients, most likely as a result of an improved response in cardiac output.

Stress echocardiography in heart failure

Echocardiography has the ability to noninvasively explore hemodynamic variables during pharmacologic or exercise stress test in patients with heart failure. In this review, we detail some important potential applications of stress echocardiography in patients with heart failure. In patients with coronary artery disease and chronic LV dysfunction, dobutamine stress echocardiography is able to distinguish between viable and fibrotic tissue to make adequate clinical decisions. Exercise testing, in combination with echocardiographic monitoring, is a method of obtaining accurate information in the assessment of functional capacity and prognosis. Functional mitral regurgitation is a common finding in patients with dilated and ischaemic cardiomyopathy and stress echocardiography in the form of exercise or pharmacologic protocols can be useful to evaluate the behaviour of mitral regurgitation. It is clinical useful to search the presence of contractile reserve in non ischemic dilated cardiomyopathy such as to screen or monitor the presence of latent myocardial dysfunction in patients who had exposure to cardiotoxic agents. Moreover, in patients with suspected diastolic heart failure and normal systolic function, exercise echocardiography could be able to demonstrate the existence of such dysfunction and determine that it is sufficient to limit exercise tolerance. Finally, in the aortic stenosis dobutamine echocardiography can distinguish severe from non-severe stenosis in patients with low transvalvular gradients and depressed left ventricular function.

Early carotid atherosclerosis and cardiac diastolic abnormalities in hypertensive subjects

Despite the fact that it is known that hypertension may be associated to early atherosclerosis manifestations, few data are to date available on the relationship between early carotid abnormalities and left ventricular diastolic dysfunction. To address this issue, 142 hypertensive patients (64 females and 78 males) younger than 55 years, at the first diagnosis of mild-to-moderate essential hypertension (WHO/ISH criteria), were selected from a database consisting of 3541 subjects referred to ultrasound cardiovascular laboratory in the last 5 years. Carotid intima-media thickness (IMT) was detected by high-resolution vascular ultrasound and left ventricular structure and function by the use of Doppler echocardiography. According to carotid IMT values, all patients were subgrouped into two groups consisting of 89 (62.6%) pts with IMT > or = 1 mm (A) and 53 (37.4%) pts with IMT < 1 mm (B). Our results show that isovolumic relaxation time (IVRT), deceleration time of E velocity (EDT) and left ventricular relative wall thickness (LV-RWT) were significantly (P < 0.05) higher in group A (IVRT 112 +/- 8.9 ms; EDT 288 +/- 21.8 ms; LV-RWT 0.40 +/- 0.08) than in group B (IVRT 92.3 +/- 4.6 ms; EDT 203.3 +/- 27.01 ms; LV- RWT 0.37 +/- 0.06). Moreover, the prevalence of left ventricular hypertrophy (LVH) was significantly (P < 0.01) higher in group A (30/89; 33.7%) than in group B (8/53; 15%). A positive correlation (P < 0.001) between IMT, EDT and IVRT was found only in hypertensives without LVH. These results are consistent with the indication that IMT evaluation has to be recommended both in hypertensive patients with LVH and in those without LVH, but with left ventricular diastolic dysfunction. This approach might improve the prognostic stratification of hypertensive subjects and it might be suitable to recognize the subset of patients at a higher risk of cardiovascular disease or events early.

Left ventricular diastolic dysfunction and diastolic heart failure

Thirty to fifty percent of patients presenting with signs and symptoms of heart failure have a normal left ventricular (LV) systolic ejection fraction. The clinical examination cannot distinguish these patients (diastolic heart failure) from those with a depressed ejection fraction (systolic heart failure), but echocardiography can. The management of diastolic heart failure has two major objectives. The first is to reverse the consequences of diastolic dysfunction (e.g., venous congestion), and the second is to eliminate or reduce the factors responsible for diastolic dysfunction (e.g., myocardial hypertrophy, fibrosis, and ischemia).

Diastolic heart failure: The forgotten manifestation of hypertensive heart disease

Heart failure (HF) is a progressively debilitating disorder characterized by frequent hospital admissions and high annual mortality rates. Coronary artery disease (CAD), hypertension, and aging are major risk factors for the development/progression of HF. For years, most of the attention has been focused on HF caused by reduced left ventricular (LV) systolic function, largely attributable to CAD. It is now generally accepted that nearly 50% of elderly patients with HF might have normal or preserved LV systolic function. This condition is commonly referred to as a distinct type of HF caused by LV diastolic dysfunction, and it often accompanies hypertensive heart disease. Isolated diastolic HF is increasingly recognized as the dominant cause of symptoms and hospitalizations from HF in a large proportion of individuals aged 65 and older. However, the clinicians caring for patients with diastolic HF do not fully understand its cause, how it progresses, or how it could be appropriately diagnosed and treated. Because varying degrees of systolic and diastolic dysfunction might coexist in any individual patient, and given the limitation of current diagnostic tools, the overall impact of isolated diastolic HF continues to evolve. Ongoing clinical trials are testing new strategies for treatment of diastolic HF.

Approach to the patient with chest pain and nonobstructive coronary artery disease

Patients with chest pain and nonobstructive coronary artery disease (NOCAD) utilize a significant part of our health care resources. Their diagnosis and treatment can often be difficult and time consuming. A simple classification system and stepwise diagnostic approach may help to reduce unnecessary testing. Also, utilization of a chest pain clinic may be beneficial for these patients.

Left ventricular diastolic function and cardiac performance during exercise in patients with acromegaly

Exercise-induced impairment of left ventricular (LV) ejection fraction is common in patients with acromegaly and normal resting systolic function. This study aimed to clarify whether diastolic dysfunction plays a role in the abnormal adaptation to exercise in these patients. Forty-eight patients with active acromegaly underwent LV radionuclide angiography at rest and during exercise. Doppler echocardiography was also performed to assess LV mass index and diastolic function by combined analysis of mitral and pulmonary flow velocity curves. LV ejection fraction at peak exercise was related to rest ejection fraction (r = 0.78; P < 0.001), peak filling rate (r = 0.55; P < 0.01), LV mass index (r = -0.56; P < 0.001), and the difference between duration of diastolic reverse pulmonary vein flow and mitral flow at atrial contraction (Delta duration) (r = -0.54; P < 0.01). At stepwise regression analysis, rest ejection fraction and Delta duration were the only variables that independently influenced (P < 0.001) ejection fraction at peak exercise. Diastolic dysfunction is important in determining cardiac performance during exercise in patients with acromegaly and normal resting systolic function. Combined analysis of pulmonary vein and mitral flow velocity curves allows the identification of impaired LV diastolic function in such patients.

Short-term training effects on left ventricular diastolic function and oxygen uptake in older and younger men

OBJECTIVE

To determine the effect of plasma volume change with short-term training and diuresis on left ventricular diastolic filling and exercise oxygen uptake (VO(2)) in older versus younger men.

METHODS

Eleven older (68 +/- 5 y) physically active (maximal oxygen uptake [VO(2max)] = 25.9 +/- 3.6 mL. kg-1. min-1) and 10 younger sedentary males (24 +/- 5 y, VO(2max) 40.5 +/- 5.0 mL. kg-1. min-1) were randomly assigned to 5 consecutive days of (1) 1 h/d high intensity stationary cycling (EXER); (2) 100 mg/d spironolactone (DIUR); and (3) exercise and diuretic (EXDI). Each treatment was separated by a 21-day washout. Doppler echocardiographic indices of left ventricular diastolic filling including peak early and atrial transmitral flow velocity and isovolumic relaxation time; percent change in plasma volume; submaximal VO(2) kinetics; and VO(2max) were determined at baseline and 48 hours after each treatment.

RESULTS

Plasma volume was increased more in the young following EXER (8.92 +/- 7.6 vs. 6.2%, P = 0.038) and decreased more in the older group following DIUR (-11.5% vs. -3.54 +/- 9.0, P < 0.001). There was no significant difference between groups after EXDI. Significant changes in peak early flow velocity with EXER in older subjects were not reflected in any other changes in left ventricular diastolic filling across conditions. No changes in left ventricular diastolic filling were observed in the young group with any condition. VO(2max) and VO(2) kinetics were unchanged under all conditions from baseline in both groups.

CONCLUSIONS

These results suggest that exercise VO(2) responses either at maximal or submaximal workrates are not limited by alterations in left ventricular pump function in physically fit older adults.

Left ventricular regional variations in myosin isoform shift in Dahl salt-sensitive hypertensive rats

To evaluate the effects of chronic pressure overload on different parts of the left ventricle (LV), we examined a myosin isoform shift from V1 to V3 as a biochemical marker of LV hypertrophy in Dahl salt-sensitive (DS) rats. Six-week-old DS rats were fed an 8% (high salt, HS; n = 24) or a 0.3% (low salt, LS; n = 12) NaCl diet. After 2 or 4 weeks, the hearts were dissected and the LVs were separated into four parts (the base and mid-portion of the interventricular septum (IVS), and the base and mid-portion of the LV free wall) for isomyosin analysis. The myosin isoform shift was analyzed by pyrophosphate gel electrophoresis. Both blood pressure and LV/body weight ratio were clearly increased in the HS group. The myosin isoform shift from V1 to V3, which was measured as a decrease in the percentage of V1 isomyosin, was demonstrated only in the base of LV, with significant predominance in the IVS at 2 weeks and in all four parts at 4 weeks in the HS group. In the LS group, a myosin isoform shift was demonstrated only in the basal portion of the LV at 4 weeks. We concluded that, in rats with salt-induced hypertension, the myosin isoform shift from V1 to V3 starts at the base of the LV, and particularly at the base of the IVS, and then spreads across the entire LV. These results suggest that pressure overload from hypertension may be strongest at the base of the IVS, and that LV hypertrophy may originate at the IVS base.

Analysis of global systolic and diastolic left ventricular performance using volume-time curves by real-time three-dimensional echocardiography

BACKGROUND

Left ventricular (LV) volume-time curves (VTC) have been described to provide quantitative data on the dynamics of global LV performance beyond ejection fraction. However, generation of VTCs by conventional 2-dimensional imaging techniques is inherently limited because of inaccurate geometric volume assumptions. We, therefore, studied whether the new concept of volumetric scanning as realized by real-time 3-dimensional echocardiography (RT-3DE) can be used to provide accurate VTCs.

METHODS

In 30 healthy participants, VTCs were generated from 18 to 24 absolute LV volumes per second by transthoracic RT-3DE and compared with magnetic resonance imaging (MRI) used for reference. LVs were traced manually in 9 to 11 parallel, short-axis planes and volumes calculated by disk method. From VTCs, we determined peak ejection rate (PER), peak early filling rate (PFR), time to PER and PFR, and end-diastolic and end-systolic volumes. For initial clinical application, 2 patient groups of coronary (n = 15) and hypertensive heart disease (n = 16) were studied.

RESULTS

In healthy participants, VTCs agreed with MRI (mean errors: PER, -39 +/- 67 mL/s; PFR, -18 +/- 84 mL/s; time to PER, 8 +/- 21 milliseconds; time to PFR 4 +/- 18 milliseconds [not significant vs 0]) whereas VTCs in coronary and hypertensive groups revealed significantly impaired diastolic function. Scanning time for VTCs was only 1 to 2 minutes by RT-3DE and 8 +/- 2 minutes by MRI (P <.001) and time for offline analysis was 22 +/- 5 minutes versus 24 +/- 4 minutes by MRI (not significant).

CONCLUSIONS

Generation of VTCs by RT-3DE is feasible and shows excellent agreement with MRI used for reference. Thus, VTCs by RT-3DE is a promising new approach providing access to quantitative information on global LV performance such as LV filling rates that is currently unavailable for the cardiologist.