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

Acute dissection of a syphilitic saccular aneurysm of the ascending aorta and arch in a hypertensive patient - a rare phenomenon

We report the case of a 77-year-old male who suffered from hypertension and died suddenly. At autopsy, he was found to have hypertensive cardiomegaly and a dissecting syphilitic saccular aneurysm of the ascending aorta and arch with tamponade. Chronic aortic regurgitation, which is often seen in syphilitic aortitis, produces an additive effect to the concentric left ventricular hypertrophy seen in hypertension.

Prevalence and Risk Factors of Mitral, Tricuspid, and Aortic Regurgitation: A Population-Based Study from Rural Northeast China

The population-based studies on the epidemiologic features of valvular regurgitation in Northeast China are scarce. We aim to estimate the prevalence and risk factors of mitral regurgitation (MR), tricuspid regurgitation (TR), and aortic regurgitation (AR) in a general population from rural Northeast China. Valvular regurgitation was assessed by color flow Doppler echocardiography in a population-based survey of 11,278 participants aged ≥35 years in rural areas of Liaoning Province during 2012 to 2013. The prevalence of mild or greater MR and TR were 1.6% and 1.5%, respectively. Trace or greater AR was present in 4.1% of the participants. In the multivariable regression model, older age, left atrial dimension, low left ventricular (LV) ejection fraction, and fasting plasma glucose were associated with higher risk of MR in men, whereas only older age and left atrial dimension increased the risk in women. Body mass index was found to be a protective factor for MR in women (odds ratio 0.847, 95% confidence interval 0.741 to 0.969). TR was independently associated with age, heart rate, low LV ejection fraction, current drinking status, and high-density lipoprotein cholesterol. The risk for AR significantly increased with age in both genders. LV mass index and aortic dimension increased the risk of AR in males, and females with higher LV mass index and high-density lipoprotein cholesterol had an increased risk for AR. In both genders, systolic blood pressure presented as a risk factor for AR, while diastolic blood pressure as a protective factor. In this large Chinese population-based study, we found remarkably low prevalence of valvular regurgitation, adding evidence for estimating disease burden and making policy strategies in Northeast China.

Additive effects of mitral regurgitation on left ventricular strain in essential hypertensive patients as evaluated by cardiac magnetic resonance feature tracking

Objectives

Hypertension is one of the leading risk factors for cardiovascular disease. Mitral regurgitation (MR) is a heart valve disease commonly seen in hypertensive cases. This study aims to assess the effect of MR on left ventricle (LV) strain impairment among essential hypertensive cases and determine factors that independently impact the global peak strain of the LV.

Materials and methods

We enrolled 184 essential hypertensive patients, of which 53 were patients with MR [HTN (MR +) group] and 131 were without MR [HTN (MR−) group]. Another group of 61 age-and gender-matched controls was also included in the study. All participants had received cardiac magnetic resonance examination. The HTN (MR +) group was classified into three subsets based on regurgitation fraction, comprising mild MR (n = 22), moderate MR (n = 19), and severe MR (n = 12). We compared the LV function and strain parameters across different groups. Moreover, we performed multivariate linear regression to determine the independent factors affecting LV global radial peak strain (GRS), circumferential peak strain (GCS), and global longitudinal peak strain (GLS).

Results

HTN (MR−) cases exhibited markedly impaired GLS and peak diastolic strain rate (PDSR) but preserved LV ejection fraction (LVEF) compared to the controls. However, HTN (MR +) patients showed a decrease in LVEF and further deteriorated GRS, GCS, GLS, PDSR, and the peak systolic strain rate (PSSR) compared to the HTN (MR−) group and controls. With increasing degrees of regurgitation, the LV strain parameters were gradually reduced in HTN (MR +) patients. Even the mild MR group showed impaired GCS, GLS, PDSR, and PSSR compared to the HTN (MR−) group. Multiple regression analyses indicated that the degree of regurgitation was independently associated with GRS (β = -0.348), GCS (β = -0.339), and GLS (β = -0.344) in HTN (MR +) patients.

Conclusion

GLS was significantly impaired in HTN (MR−) patients. MR may further exacerbate the deterioration of LV strain among essential hypertensive cases. Besides, the degree of regurgitation was independently correlated with GRS, GCS, and GLS in HTN (MR +) patients.

The Role of Arterial Hypertension in Mitral Valve Regurgitation

PURPOSE OF REVIEW

To review medical literature for evidence of association between hypertension and mitral regurgitation (MR) and summarize potential favorable effects of antihypertensive drugs on MR natural history and treatment.

RECENT FINDINGS

Hypertension and MR are common diseases affecting a large proportion of the general population. Contemporary evidence suggests that hypertension may worsen the progression and prognosis of MR through augmented mechanical stress and increased regurgitation volume. Renin-angiotensin axis inhibitors, beta-blockers, and vasodilators have been tested in order to prevent or decrease primary or secondary MR. Although antihypertensive agents may improve hemodynamic parameters and left ventricular remodeling in primary MR, there is no strong evidence of benefit on clinical outcomes. On the other hand, a beneficial effect of these drugs on secondary MR is better established. Moreover, there are no studies evaluating a possible benefit of lower blood pressure targets in MR. Randomized controlled trials are warranted to elucidate the precise role of antihypertensive therapy on treatment of MR.

Ankylosing Spondylitis Is Associated with Increased Prevalence of Left Ventricular Hypertrophy

OBJECTIVE

Ankylosing spondylitis (AS) is associated with increased risk for cardiovascular disease (CVD). Left ventricular (LV) hypertrophy is a strong precursor for clinical CVD. The aim of our study was to assess whether having AS was associated with increased prevalence of LV hypertrophy.

METHODS

Clinical and echocardiographic data from 139 AS patients and 126 age- and sex-matched controls was used. LV mass was calculated according to guidelines and indexed to height^2.7. LV hypertrophy was considered present if LV mass index was > 49.2 g/m^2.7 in men and > 46.7 g/m^2.7 in women.

RESULTS

Patients with AS were on average 49 ± 12 years old, and 60% were men. The prevalence of hypertension (HTN; 35% vs 41%) and diabetes (5% vs 2%) was similar among patients and controls, while patients with AS had higher serum C-reactive protein level (CRP; p < 0.001). The prevalence of LV hypertrophy was higher in patients with AS compared to controls (15% vs 6%, p = 0.01). In multivariable logistic regression analysis, having AS was associated with OR 6.3 (95% CI 2.1-19.3, p = 0.001) of having LV hypertrophy independent of the presence of HTN, diabetes, and obesity. In multivariable linear regression analyses, having AS was also associated with higher LV mass (β 0.15, p = 0.007) after adjusting for CVD risk factors including sex, body mass index, systolic blood pressure, diabetes, and serum CRP (multiple R² = 0.41, p < 0.001).

CONCLUSION

Having AS was associated with increased prevalence of LV hypertrophy independent of CVD risk factors. This finding strengthens the indication for thorough CVD risk assessment in patients with AS.

Mitral apparatus assessment by delayed enhancement CMR: relative impact of infarct distribution on mitral regurgitation

OBJECTIVES

This study sought to assess patterns and functional consequences of mitral apparatus infarction after acute myocardial infarction (AMI).

BACKGROUND

The mitral apparatus contains 2 myocardial components: papillary muscles and the adjacent left ventricular (LV) wall. Delayed-enhancement cardiac magnetic resonance (DE-CMR) enables in vivo study of inter-relationships and potential contributions of LV wall and papillary muscle infarction (PMI) to mitral regurgitation (MR).

METHODS

Multimodality imaging was performed: CMR was used to assess mitral geometry and infarct pattern, including 3D DE-CMR for PMI. Echocardiography was used to measure MR. Imaging occurred 27 ± 8 days after AMI (CMR, echocardiography within 1 day).

RESULTS

A total of 153 patients with first AMI were studied; PMI was present in 30% (n = 46 [72% posteromedial, 39% anterolateral]). When stratified by angiographic culprit vessel, PMI occurred in 65% of patients with left circumflex, 48% with right coronary, and only 14% of patients with left anterior descending infarctions (p <0.001). Patients with PMI had more advanced remodeling as measured by LV size and mitral annular diameter (p <0.05). Increased extent of PMI was accompanied by a stepwise increase in mean infarct transmurality within regional LV segments underlying each papillary muscle (p <0.001). Prevalence of lateral wall infarction was 3-fold higher among patients with PMI compared to patients without PMI (65% vs. 22%, p <0.001). Infarct distribution also impacted MR, with greater MR among patients with lateral wall infarction (p = 0.002). Conversely, MR severity did not differ on the basis of presence (p = 0.19) or extent (p = 0.12) of PMI, or by angiographic culprit vessel. In multivariable analysis, lateral wall infarct size (odds ratio 1.20/% LV myocardium [95% confidence interval: 1.05 to 1.39], p = 0.01) was independently associated with substantial (moderate or greater) MR even after controlling for mitral annular (odds ratio 1.22/mm [1.04 to 1.43], p = 0.01), and LV end-diastolic diameter (odds ratio 1.11/mm [0.99 to 1.23], p = 0.056).

CONCLUSIONS

Papillary muscle infarction is common after AMI, affecting nearly one-third of patients. Extent of PMI parallels adjacent LV wall injury, with lateral infarction-rather than PMI-associated with increased severity of post-AMI MR.

Valvular regurgitation impact on left ventricular 2-dimensional and Doppler echocardiographic indices in patients with essential hypertension

BACKGROUND

Blacks have both a higher hypertension prevalence and accelerated cardiac end organ damage. Because blacks also have a higher prevalence of valvular heart disease, which occurs at a younger age than for whites, we further examined the contribution of valvular regurgitation to the severity of hypertensive heart disease in Nigerians.

METHODS

We evaluated and compared echocardiographic indexes in 75 essential hypertensive Nigerians with (n=48) and without (n=27) valvular regurgitations. Demographic and echocardiographic indices, as well as the types and severity of valvular lesions were compared between the groups using bivariate logistic regression and analysis of variance.

RESULTS

The 2 groups were of similar demographics, but those with regurgitations had larger cardiac size (p < .05), greater mass (147 +/- 31 vs. 122 +/- 32 g/m2, p = .01) higher volume (p < .01), and left atrial size (35.6 +/- 4.6 vs. 33.3 +/- 4.6 mm, p < .05). Atrial size, cardiac volume, and dimension were independent correlates/predictors of regurgitation occurrence. Relative wall thickness of at least 0.6 was more common in regurgitation patients. Cardiac mass was correlated to increasing age (r = 0.23, p = .043). The valvular lesions frequencies were aortic regurgitation, 8; mitral regurgitation, 22; and mixed, 18. The aortic orifice dimension was significantly different among the regurgitant cases, highest in aortic regurgitation (p = .001). Aortic orifice dimension increased with hypertension duration (p = .028).

CONCLUSIONS

Regurgitant lesions are common and occur early in hypertensive Africans. Apparently mild valvular regurgitation may accentuate preclinical concentric hypertrophy in hypertensive blacks.

Factors influencing left ventricular structure and stress-corrected systolic function in men and women with asymptomatic aortic valve stenosis (a SEAS Substudy)

To identify determinants of left ventricular (LV) structure and stress-corrected systolic function in men and women with asymptomatic aortic stenosis (AS), Doppler echocardiography was performed at baseline in 1,046 men and 674 women 28 to 86 years of age (mean 67 +/- 10) recruited in the Simvastatin Ezetimibe in Aortic Stenosis (SEAS) study evaluating placebo-controlled combined simvastatin and ezetimibe treatment in AS. LV hypertrophy was less prevalent in women despite older age, higher systolic blood pressure, and smaller aortic valve area/body surface area (all p values <0.05). In logistic regression analyses, LV hypertrophy was independently associated with male gender, severity of AS, hypertension, higher systolic blood pressure, and lower stress-corrected midwall shortening (scMWS) or stress-corrected fractional shortening (scFS; all p values <0.01). In men aortic regurgitation also was a predictor of LV hypertrophy (p <0.05). Women had greater scFS and scMWS when corrected for LV size or geometry (all p values <0.001). In multivariate analyses, female gender predicted 11% greater scFS and 4% greater scMWS independent of age, body mass index, heart rate, aortic valve area, LV mass, relative wall thickness, aortic regurgitation, hypertension, and end-systolic stress (R(2) = 0.23 and 0.59, respectively, p <0.001). In conclusion, the major determinants of LV hypertrophy in patients with asymptomatic AS are male gender, severity of AS, and concomitant hypertension. Women have higher stress-corrected indexes of systolic function independent of LV geometry or size, wall stress, older age, or more concomitant hypertension.

Prevalence of Unsuspected and Significant Mitral and Aortic Regurgitation

OBJECTIVE

We sought to determine the prevalence of unsuspected, pre-existing valvular regurgitation in a large, heterogeneous population of patients referred for an echocardiogram.

METHODS

The echocardiograms of 6851 consecutive individuals without suspected valve disease were reviewed. Regurgitant severity was graded using a clinical composite of published methods and multiple logistic analyses were used to model various clinical variables.

RESULTS

The overall prevalence of moderate or greater mitral regurgitation (MR) was 11.7% in male patients and 12.5% in female patients. For mild or greater aortic insufficiency (AI), the prevalence was 18.9% in male patients and 19.7% in female patients. Both MR and AI increased exponentially as a function of age. Female sex predicted MR, but AI was sex neutral. Regurgitant severity increased with decreasing ejection fraction and body mass index, a history of hypertension, the presence of left ventricular hypertrophy, and valvular abnormalities.

CONCLUSIONS

The prevalence of unsuspected MR and AI is substantial, increases exponentially with age, and is predicted by commonly used clinical variables.

Predictive value of heart-type fatty acid-binding protein for left ventricular remodelling and clinical outcome of hypertensive patients with mild-to-moderate aortic valve diseases

Heart-type fatty acid-binding protein (H-FABP), a marker of acute myocardial infarction and a soluble cytosolic protein, may be released following left ventricular remodelling in cardiac overloaded hearts caused by hypertension, aortic regurgitation (AR) or aortic stenosis (AS). Our aim was to investigate if H-FABP levels are associated with left ventricular remodelling and clinical outcome in hypertensive patients with AR or AS. H-FABP and brain natriuretic peptide (BNP) were measured, glomerular filtration rate (GFR) was estimated using the modification of diet in renal disease (MDRD) equation, and left ventricular dimension at systole corrected for body surface area (LVDs/BSA) and relative wall thickness (RWT) were determined by echocardiography in hypertensive patients with mild-to-moderate AR (n=78), those with mild-to-moderate AS (n=73) and those without valvular heart diseases (HT) (n=50). H-FABP levels were significantly higher in AR (4.9+/-3 ng/ml) and in AS (4.5+/-3) than in HT (3.4+/-1) and BNP (65+/-73 pg/ml, 76+/-75, 35+/-22). H-FABP correlated with LVDs/BSA in AR (beta=0.23, P<0.05), and RWT in AS (beta=0.18, P<0.05) after adjustment for age, gender and all the other variables. AS and AR patients were prospectively followed up for cardiac events during 34+/-19 months. A multivariate Cox hazard analysis indicated H-FABP was an independent predictor of outcome both in AR (relative risk (RR)=7.61, 95% CI=2.39-25.3) and AS (RR=13.6, 95% CI=3.27-66.9). H-FABP, associated with left ventricular remodelling, is useful in predicting clinical outcome in hypertensive patients with mild-to-moderate aortic valve diseases.

Planar biaxial creep and stress relaxation of the mitral valve anterior leaflet

A fundamental assumption in mitral valve (MV) therapies is that a repaired or replaced valve should mimic the functionality of the native valve as closely as possible. Thus, improvements in valvular treatments are dependent on the establishment of a complete understanding of the function and mechanical properties of the native normal MV. In a recent study [Grashow et al. ABME 34(2), 2006] we demonstrated that the planar biaxial stress-strain relationship of the MV anterior leaflet (MVAL) exhibited minimal hysteresis and a stress-strain response independent of strain rate, suggesting that MVAL could be modeled as a "quasi-elastic" material. The objective of our current study was to expand these results to provide a more complete picture of the time-dependent mechanical properties of the MVAL. To accomplish this, biaxial stress-relaxation and creep studies were performed on porcine MVAL specimens. Our primary finding was that while the MVAL leaflet exhibited significant stress relaxation, it exhibited negligible creep over the 3-h test. These results furthered our assertion that the MVAL functionally behaves not as a linear or non-linear viscoelastic material, but as an anisotropic quasi-elastic material. These results appear to be unique in the soft tissue literature; suggesting that valvular tissues are unequalled in their ability to withstand significant loading without time-dependent material effects. Moreover, insight into these specialized characteristics can help guide and inform efforts directed toward surgical repair and engineered valvular tissue replacements.