Remodeling in Aortic Stenosis With Reduced and Preserved Ejection Fraction: Insight on Motion Abnormality Via 3D + Time Personalized LV Modeling in Cardiac MRI

BACKGROUND

Increased afterload in aortic stenosis (AS) induces left ventricle (LV) remodeling to preserve a normal ejection fraction. This compensatory response can become maladaptive and manifest with motion abnormality. It is a clinical challenge to identify contractile and relaxation dysfunction during early subclinical stage to prevent irreversible deterioration.

PURPOSE

To evaluate the changes of regional wall dynamics in 3D + time domain as remodeling progresses in AS.

STUDY TYPE

Retrospective.

POPULATION

A total of 31 AS patients with reduced and preserved ejection fraction (14 AS_rEF: 7 male, 66.5 [7.8] years old; 17 AS_pEF: 12 male, 67.0 [6.0] years old) and 15 healthy (6 male, 61.0 [7.0] years old).

FIELD STRENGTH/SEQUENCE

1.5 T Magnetic resonance imaging/steady state free precession and late-gadolinium enhancement sequences.

ASSESSMENT

Individual LV models were reconstructed in 3D + time domain and motion metrics including wall thickening (TI), dyssynchrony index (DI), contraction rate (CR), and relaxation rate (RR) were automatically extracted and associated with the presence of scarring and remodeling.

STATISTICAL TESTS

Shapiro-Wilk: data normality; Kruskal-Wallis: significant difference (P < 0.05); ICC and CV: variability; Mann-Whitney: effect size.

RESULTS

AS_rEF group shows distinct deterioration of cardiac motions compared to AS_pEF and healthy groups (TIAS_rEF : 0.92 [0.85] mm, TIAS_pEF : 5.13 [1.99] mm, TIhealthy : 3.61 [1.09] mm, ES: 0.48-0.83; DIAS_rEF : 17.11 [7.89]%, DIAS_pEF : 6.39 [4.04]%, DIhealthy : 5.71 [1.87]%, ES: 0.32-0.85; CRAS_rEF : 8.69 [6.11] mm/second, CRAS_pEF : 16.48 [6.70] mm/second, CRhealthy : 10.82 [4.57] mm/second, ES: 0.29-0.60; RRAS_rEF : 8.45 [4.84] mm/second; RRAS_pEF : 13.49 [8.56] mm/second, RRhealthy : 9.31 [2.48] mm/second, ES: 0.14-0.43). The difference in the motion metrics between healthy and AS_pEF groups were insignificant (P-value = 0.16-0.72). AS_rEF group was dominated by eccentric hypertrophy (47.1%) with concomitant scarring. Conversely, AS_pEF group was dominated by concentric remodeling and hypertrophy (71.4%), which could demonstrate hyperkinesia with slight wall dyssynchrony than healthy. Dysfunction of LV mechanics corresponded to the presence of myocardial scarring (54.9% in AS), which reverted the compensatory mechanisms initiated and performed by LV remodeling.

DATA CONCLUSION

The proposed 3D + time modeling technique may distinguish regional motion abnormalities between AS_pEF, AS_rEF, and healthy cohorts, aiding clinical diagnosis and monitoring of AS progression. Subclinical myocardial dysfunction is evident in early AS despite of normal EF.

LEVEL OF EVIDENCE

4 TECHNICAL EFFICACY: Stage 1.

Metabolic surgery in improving arterial health in obese individuals

PURPOSE

Arterial stiffness has gained recognition as a stand-alone risk factor for cardiovascular disease (CVD). Obesity is intricately linked to elevated arterial stiffness, the development of left ventricular (LV) hypertrophy, and the emergence of diastolic dysfunction, all of which collectively contribute substantially to an unfavorable prognosis. Weight loss has become a standard recommendation for all patients with CVD concurrent with morbid obesity; however, randomized evidence to support this recommendation was limited earlier. The latest scientific studies revealed dynamic changes in aortic stiffness after substantial weight loss by bariatric surgery, also known as metabolic surgery, in patients with obesity. There is also a favorable evolution in LV hypertrophy and a significant impact on arterial hypertension and other promising cardiovascular outcomes in obese people after bariatric surgery.

METHODS/RESULTS

We aimed to examine the cardiovascular effects of various metabolic surgeries in morbidly obese individuals, especially their role in improving arterial health, the potential impact on surrogate markers of atherosclerotic vascular disease, and consequently reducing the likelihood of cardiovascular events.

CONCLUSION

In conclusion, metabolic surgery is associated with a significant decrease in the occurrence of major adverse cardiovascular events (MACE) and all-cause mortality among obese individuals, alongside remarkable enhancement of arterial health. These findings underscore the critical importance of implementing strategies to combat obesity and reduce adiposity within the general population.

Fibroblast growth factor 23 as a biomarker of right ventricular dysfunction in pulmonary hypertension

BACKGROUND

Fibroblast growth factor 23 (FGF-23) has been associated with left ventricular hypertrophy (LVH) and heart failure. However, its role in right ventricular (RV) remodeling and RV failure is unknown. This study analyzed the utility of FGF-23 as a biomarker of RV function in patients with pulmonary hypertension (PH).

METHODS

In this observational study, FGF-23 was measured in the plasma of patients with PH (n = 627), dilated cardiomyopathy (DCM, n = 59), or LVH with severe aortic stenosis (n = 35). Participants without LV or RV abnormalities served as controls (n = 36).

RESULTS

Median FGF-23 plasma levels were higher in PH patients than in healthy controls (p < 0.001). There were no significant differences between PH, DCM, and LVH patients. Analysis across tertiles of FGF-23 levels in PH patients revealed an association between higher FGF-23 levels and higher levels of NT-proBNP and worse renal function. Furthermore, patients in the high-FGF-23 tertile had a higher pulmonary vascular resistance (PVR), mean pulmonary artery pressure, and right atrial pressure and a lower cardiac index (CI) than patients in the low tertile (p < 0.001 for all comparisons). Higher FGF-23 levels were associated with higher RV end-diastolic diameter and lower tricuspid annular plane systolic excursions (TAPSE) and TAPSE/PASP. Receiver operating characteristic analysis revealed FGF-23 as a good predictor of RV maladaptation, defined as TAPSE < 17 mm and CI < 2.5 L/min/m2. Association of FGF-23 with parameters of RV function was independent of the glomerular filtration rate in regression analysis.

CONCLUSION

FGF-23 may serve as a biomarker for maladaptive RV remodeling in patients with PH.

Effects of myocardial sheetlet sliding on left ventricular function

Left ventricle myocardium has a complex micro-architecture, which was revealed to consist of myocyte bundles arranged in a series of laminar sheetlets. Recent imaging studies demonstrated that these sheetlets re-orientated and likely slided over each other during the deformations between systole and diastole, and that sheetlet dynamics were altered during cardiomyopathy. However, the biomechanical effect of sheetlet sliding is not well-understood, which is the focus here. We conducted finite element simulations of the left ventricle (LV) coupled with a windkessel lumped parameter model to study sheetlet sliding, based on cardiac MRI of a healthy human subject, and modifications to account for hypertrophic and dilated geometric changes during cardiomyopathy remodeling. We modeled sheetlet sliding as a reduced shear stiffness in the sheet-normal direction and observed that (1) the diastolic sheetlet orientations must depart from alignment with the LV wall plane in order for sheetlet sliding to have an effect on cardiac function, that (2) sheetlet sliding modestly aided cardiac function of the healthy and dilated hearts, in terms of ejection fraction, stroke volume, and systolic pressure generation, but its effects were amplified during hypertrophic cardiomyopathy and diminished during dilated cardiomyopathy due to both sheetlet angle configuration and geometry, and that (3) where sheetlet sliding aided cardiac function, it increased tissue stresses, particularly in the myofibre direction. We speculate that sheetlet sliding is a tissue architectural adaptation to allow easier deformations of the LV walls so that LV wall stiffness will not hinder function, and to provide a balance between function and tissue stresses. A limitation here is that sheetlet sliding is modeled as a simple reduction in shear stiffness, without consideration of micro-scale sheetlet mechanics and dynamics.

Left ventricular mass regression after aortic valve replacement with the TTK Chitra™ monoleaflet tilting disc valve

Objective

To study the extent of left ventricular (LV) mass regression in aortic stenosis after aortic valve replacement with the TTK Chitra™ tilting disc valve.

Methods and materials

This study included patients with severe isolated aortic stenosis (AS), admitted in our department. They had aortic valve replacement (AVR) with the TTK Chitra™ tilting disc valve, between January 2008 and December 2010. Data were collected from consecutive forty-eight patients. LV mass and diametric and functional parameters were recorded preoperatively and compared with echocardiography after 3 months, 6 months, then yearly, up to 3 years.

Results

70.8% of the patients were males and 29.2% were females. The mean duration of illness was 37.92 ± 25.87 months. The mean LV ejection fraction increased 3 months after surgery (61.56 ± 10.10% to 69.31 ± 9.34%) with a sustained increase for the next 3 years. The mean LV end-diastolic diameter decreased (50.16 ± 6.05 mm to 45.69 ± 5.93 mm) after 3 months of surgery, with a sustained decrease for the next 3 years. The mean LV end-systolic diameter decreased (32.84 ± 6.96 mm to 29.41 ± 5.86 mm) after 3 months of surgery and then showed a sustained decrease for the next 3 years. The LV mass assessed with echocardiography regressed from 324.65 ± 97.77 g before surgery to 252.64 ± 71.12 g after 3 months and then showed a sustained decrease over the next 3 years.

Conclusion

Significant LV mass regression occurred after AVR with the TTK Chitra™ valve. The maximum reversal was found to be within the first 3 months after surgery with sustained beneficial improvement for the next 3 years.

Defining left ventricular remodeling using lean body mass allometry: a UK Biobank study

PURPOSE

The geometric patterns of ventricular remodeling are determined using indexed left ventricular mass (LVM), end-diastolic volume (LVEDV) and concentricity, most often measured using the mass-to-volume ratio (MVR). The aims of this study were to validate lean body mass (LBM)-based allometric coefficients for scaling and to determine an index of concentricity that is independent of both volume and LBM.

METHODS

Participants from the UK Biobank who underwent both CMR and dual-energy X-ray absorptiometry (DXA) during 2014-2015 were considered (n = 5064). We excluded participants aged ≥ 70 years or those with cardiometabolic risk factors. We determined allometric coefficients for scaling using linear regression of the logarithmically transformed ventricular remodeling parameters. We further defined a multiplicative allometric relationship for LV concentricity (LVC) adjusting for both LVEDV and LBM.

RESULTS

A total of 1638 individuals (1057 female) were included. In subjects with lower body fat percentage (< 25% in males, < 35% in females, n = 644), the LBM allometric coefficients for scaling LVM and LVEDV were 0.85 ± 0.06 and 0.85 ± 0.03 respectively (R² = 0.61 and 0.57, P < 0.001), with no evidence of sex-allometry interaction. While the MVR was independent of LBM, it demonstrated a negative association with LVEDV in (females: r = - 0.44, P < 0.001; males: - 0.38, P < 0.001). In contrast, LVC was independent of both LVEDV and LBM [LVC = LVM/(LVEDV^0.40 × LBM^0.50)] leading to increased overlap between LV hypertrophy and higher concentricity.

CONCLUSIONS

We validated allometric coefficients for LBM-based scaling for CMR indexed parameters relevant for classifying geometric patterns of ventricular remodeling.

How Do Young and Old Spontaneously Hypertensive Rats Respond to Antihypertensive Therapy? Comparative Studies on the Effects of Combined Captopril and Nifedipine Treatment

Numerous studies on the effects of antihypertensive treatment in young spontaneously hypertensive rats (SHRs) have shown that early-onset therapy may effectively reduce their blood pressure (BP) even to normotensive values. In contrast, only a few studies investigated the effects of treatment started at an advanced age. These studies revealed that antihypertensive effects are lower in adult or even in senescent SHRs compared with young SHRs. Even more, prevention of cardiac sequelae of hypertension such as hypertrophy and fibrosis is less effective when treatment starts late in life. Because, in patients, combination therapies with calcium antagonists are favored, we studied the efficacy of a combination therapy with captopril and nifedipine in young and old SHRs. We directly compared the treatment effects on BP as well as on cardiac hypertrophy and remodeling between these two animal cohorts. With antihypertensive treatment, significantly lower BP values were achieved in young SHRs despite a shorter treatment period compared with old SHRs. Although treatment effects on cardiac hypertrophy were greater in old than in young SHRs, cardiac fibrosis was significantly attenuated only in young but not in old SHRs. The results emphasize the value of antihypertensive therapy and particularly accentuate the importance of an early-onset therapy. With respect to problems such as late diagnosis and poor therapy adherence, these results may have great importance for the treatment of human hypertension.

Epicardial Adipose Tissue Was Highly Associated with Reduction in Left Ventricular Diastolic Function as Early as in Adolescence

BACKGROUND

Epicardial adipose tissue (EAT) is increased in adolescents with obesity and may play a role in early cardiovascular pathophysiological changes. There is a lack of evidence focusing on the association between EAT and cardiac function in adolescents. This study explored associations between EAT, left ventricle (LV) geometric, and LV functional changes in adolescents.

METHODS

Adolescent volunteers between 10 and 20 years of age were included. Body mass index (BMI) was presented as age- and sex-specific BMI z-scores. Blood samples for glucose metabolism, lipid profiles, and high-sensitivity C-reactive protein (hs-CRP) were obtained. EAT thickness, LV hypertrophy, and LV diastolic function were measured by echocardiography.

RESULTS

The mean age of the 276 adolescents was 13.51 ± 2.44 years. BMI z-score was strongly associated with EAT thickness (r = 0.77; p < 0.001). Multivariable analysis revealed that age, insulin resistance, total cholesterol to high-density lipoprotein cholesterol ratio, and hs-CRP were independent predictors of increased EAT thickness. After adjusting for sex, age, and BMI z-score by multivariable analysis, EAT thickness was a strong predictor of higher LV mass indexed to height^2.7, higher relative wall thickness, lower mitral annulus e'/a', and higher E/e' of the mitral annulus. There was no association between EAT and LV ejection fraction.

CONCLUSIONS

EAT was highly associated with LV hypertrophy and reduction in LV diastolic function, independent of BMI z-score in the enrolled adolescents. Of note, the negative impacts of EAT on LV geometry and diastolic function occurred as early as in adolescence. This highlights the importance of preventing obesity and EAT deposition early in life.

How Effective Is a Late-Onset Antihypertensive Treatment? Studies with Captopril as Monotherapy and in Combination with Nifedipine in Old Spontaneously Hypertensive Rats

Background: A major problem in the treatment of human hypertension is the late diagnosis of hypertension and, hence, the delayed start of treatment. Very often, hypertension has existed for a long time and cardiac damage has already developed. Therefore, we tested whether late-onset antihypertensive treatment is effective in lowering blood pressure (BP) and in reducing or even preventing left ventricular hypertrophy and fibrosis. Methods: Twenty-one male 60-week-old spontaneously hypertensive rats (SHR) were included. Fourteen rats received oral treatment with captopril (CAP) either as monotherapy or combined with nifedipine (CAP + NIF) over 22 weeks. Seven untreated SHR served as controls. We examined the therapeutic effects on BP, heart weight and histological and biochemical markers of left ventricular remodeling and fibrosis. Results: At 82 weeks of age, BP was reduced in the CAP and CAP + NIF groups by 44 and 51 mmHg, respectively (p < 0.001), but not in untreated controls. Despite the late therapy start, cardiac hypertrophy and fibrosis were attenuated compared to controls. Both treatments reduced heart weight by 1.2 mg/g (25%, p = 0.001) and collagens I and III by 66% and 60%, respectively (p < 0.001), thus proving nearly equivalent cardioprotective efficacy. Conclusion: These data clearly emphasize the benefit of antihypertensive treatment in reducing BP and mitigating the development of cardiac damage even when treatment is started late in life.

Retrospective evaluation of hypertrophic cardiomyopathy in 68 dogs

BACKGROUND

There is a lack of clinical data on hypertrophic cardiomyopathy (HCM) in dogs.

HYPOTHESIS/OBJECTIVES

To investigate signalment, clinical signs, diagnostic findings, and survival in dogs with HCM.

ANIMALS

Sixty-eight client-owned dogs.

METHODS

Retrospective multicenter study. Medical records were searched between 2003 and 2015. The diagnosis of left ventricular (LV) hypertrophy was made by echocardiographic examination.

RESULTS

Three hundred and forty-five dogs with LV hypertrophy were identified, of which 277 were excluded. The remaining 68 dogs were 0.3 to 14 years old and predominantly <10 kg (85%), and without a sex predilection. Twenty-four % were Shih Tzu and 24% terrier breeds. Most (80%) had a systolic heart murmur. Owner-determined exercise intolerance (37%) and syncope (18%) were most commonly reported signs. The majority (84%) of dogs had symmetrical LV hypertrophy, whereas asymmetrical septal and LV free wall hypertrophy was observed in 9% and 6% of dogs, respectively. Isolated basal interventricular septal hypertrophy was not observed. Commonly recorded were systolic anterior motion of the mitral valve (60%) and LV diastolic dysfunction (89% of dogs where diastolic function was evaluated). Six dogs died unexpectedly, and 3 developed congestive heart failure. Known survival times were between 1 day and 114 months after diagnosis.

CONCLUSIONS AND CLINICAL IMPORTANCE

Hypertrophic cardiomyopathy in dogs should be considered as a differential diagnosis if LV hypertrophy is identified. Small breed dogs are overrepresented, and it is uncommon for dogs with HCM to develop CHF although sudden death can occur.

Impact of left ventricular hypertrophy on clinical outcomes in patients with dialysis: a single-center study in Japan

PURPOSE

Left ventricular hypertrophy (LVH) is a well-known risk factor for poor clinical outcomes in patients undergoing dialysis. However, little evidence supports the above notion in Japan, and the influence of subtypes of LVH on prognosis.

METHODS

We investigated 367 patients undergoing dialysis who underwent routine echocardiographic examinations between April and September 2018. LVH was defined as any LV mass ≥ 115 g/m² in men and ≥ 95 g/m² in women obtained by echocardiography. The primary endpoint was a composite outcome including all-cause death, admission due to heart failure, and ischemic heart event or stroke. LVH was divided into subtype-groups according to eccentric hypertrophy or concentric hypertrophy, and with and without hypertension.

RESULTS

LVH was observed in 171 (47%) patients. The primary endpoint was observed in 58 patients (16%) during the median follow-up period of 500 days. Multivariable Cox regression analyses identified four independent risk factors for the primary endpoint: age, pulse rate, serum albumin level, and LV mass index (per 10-g/m² increase; hazard ratio: 1.12, 95% confidence interval: 1.06-1.18, P < 0.001). Kaplan-Meier analyses demonstrated that patients with LVH had a worse prognosis than those without LVH in terms of the primary endpoint (log-rank P < 0.001). The incidence of the primary outcome was not significantly different between patients with eccentric or concentric hypertrophy, and between LVH patients with and without hypertension.

CONCLUSION

Japanese patients with LVH undergoing dialysis had a worse prognosis than those without LVH in terms of the composite clinical endpoint.

Left ventricular hypertrophy in athletes, a case-control analysis of interindividual variability

BACKGROUND

A variability in cardiac remodeling is observed in athletes regardless of age, sex, body size and sport participated. We sought to investigate whether other individual characteristics could affect the extent of Left ventricular hypertrophy (LVH).

METHODS

From 2120 consecutive Olympic athletes, those with LVH (defined as LV Wall thickness ≥ 13 mm) were matched 1:1 by age, gender, body surface area and type of sport with non-LVH Athletes. Clinical and Echocardiographic variables were compared.

RESULTS

48 athletes with LVH (2.3%) and 48 matched non-LVH athletes were identified. LVH Athletes had higher body weight (90 ± 18 vs 81 ± 11Kg; p = 0.006) body mass index (26 ± 2 vs 24 ± 2 Kg/m2; p < 0.001) and body fat percentage (15 ± 7% vs 12 ± 4%; p = 0.016) compared to non-LVH Athletes. They also had higher systolic (123 ± 1 vs 116 ± 11 mmHg; p = 0.002) and diastolic blood pressure (76 ± 8 vs 71 ± 9 mmHg; p = 0.002). On exercise testing, LVH Athletes reached a lower index workload (3.7 ± 0.9 vs 4.1 ± 0.8 W/Kg; p = 0.013) and a higher peak diastolic blood pressure (79 ± 10 vs 74 ± 11 mmHg; p = 0.012) than those without LVH. Binary logistic regression analysis showed that diastolic blood pressure (OR 1.052; 95% CI from 1.011 to 1.130; p = 0.020) and BMI (OR 1.220; 95% CI from 1.016 to 1.465; p = 0.033) had the strongest association with LVH as categorical variable.

CONCLUSIONS

Our study showed that increased blood pressure at rest and during exercise, together with larger body weight, body mass and fat percentage are associated with a higher degree of LVH, which is not associated with a greater physical performance and therefore possibly disproportionate to the sport activity.

Risk factors for left ventricular dysfunction in adulthood: role of low birth weight

Aims

This study aimed to determine the relationship of low birth weight (LBW) with adult cardiac structure and function and investigate potential causal pathways.

Methods and results

A population‐based sample of 925 Australians (41.3% male) were followed from childhood (aged 7–15 years) to young adulthood (aged 26–36 years) and mid‐adulthood (aged 36–50 years). Left ventricular (LV) global longitudinal strain (GLS, %), LV mass index (LVMi, g/m^2.7), LV filling pressure (E/e′), and left atrial volume index (g/m²) were measured by transthoracic echocardiography in mid‐adulthood. Birth weight category was self‐reported in young adulthood and classified as low (≤5 lb or ≤2270 g), normal (5–8 lb or 2271–3630 g), and high (>8 lb or >3630 g). Of the 925 participants, 7.5% (n = 69) were classified as LBW. Compared with participants with normal birth weight, those with LBW had 2.01‐fold (95% confidence interval: 1.19, 3.41, P = 0.009) higher risks of impaired GLS (GLS > −18%) and 2.63‐fold (95% confidence interval: 0.89, 7.81, P = 0.08) higher risks of LV hypertrophy (LVMi > 48 g/m^2.7 in men or >44 g/m^2.7 in women) in adulthood, independent of age, sex, and any socio‐economic factors. Participants with LBW significantly increased body fat from childhood to adulthood relative to their peers and had greater levels of triglycerides, fasting glucose, and arterial stiffness in adulthood. These risk factors were the strongest mediators and explained 54% of the LBW effect size on adult GLS and 33% of the LBW effect size on LVMi. The remaining of these associations was independent of any of the measured risk factors.

Conclusions

Low birth weight was associated with impaired cardiac structure and function in mid‐adulthood. This association was only partially explained by known risk factors.

Inhibition of interleukin-6 signaling attenuates aortitis, left ventricular hypertrophy and arthritis in interleukin-1 receptor antagonist deficient mice

The aim of the present study was to examine whether inhibition of Interleukin (IL)-6 signaling by MR16-1, an IL-6 receptor antibody, attenuates aortitis, cardiac hypertrophy, and arthritis in IL-1 receptor antagonist deficient (IL-1RA KO) mice. Four weeks old mice were intraperitoneally administered with either MR16-1 or non-immune IgG at dosages that were adjusted over time for 5 weeks. These mice were stratified into four groups: MR16-1 treatment groups, KO/MR low group (first 2.0 mg, following 0.5 mg/week, n=14) and KO/MR high group (first 4.0 mg, following 2.0 mg/week, n=19) in IL-1RA KO mice, and IgG treatment groups, KO/IgG group (first 2.0 mg, following 1.0 mg/week, n=22) in IL-1RA KO mice, and wild/IgG group (first 2.0 mg, following 1.0 mg/week, n=17) in wild mice. Aortitis, cardiac hypertrophy and arthropathy were histologically analyzed. Sixty-eight percent of the KO/IgG group developed aortitis (53% developed severe aortitis). In contrast, only 21% of the KO/MR high group developed mild aortitis, without severe aortitis (P<0.01, vs KO/IgG group). Infiltration of inflammatory cells, such as neutrophils, T cells, and macrophages, was frequently observed around aortic sinus of the KO/IgG group. Left ventricle and cardiomyocyte hypertrophy were observed in IL-1RA KO mice. Administration of high dosage of MR16-1 significantly suppressed cardiomyocyte hypertrophy. MR16-1 attenuated the incidence and severity of arthritis in IL-1RA KO mice in a dose-dependent manner. In conclusion, blockade of IL-6 signaling may exert a beneficial effect to attenuate severe aortitis, left ventricle hypertrophy, and arthritis.

Congestive heart failure model representing aortic banding induced hypertrophy: A study to analyse extent of pressure overload and alteration in myocardial structure and function

Congestive Heart failure (CHF) is a severe pathology representing a major public health problem in industrialized nations which is increasing in prevalence and incidence. The aortic banding rat model provides steady progression of cardiac dysfunction under chronic pressure overload. Present study evaluated two abdominal aortic constriction techniques including constriction of aorta above renal arteries and between renal arteries. The extent of constriction was varied with 22 G and 24 G needles and the duration for evaluation of CHF was also varied by terminating the banded animals after 6 and 8 weeks of banding. Various hemodynamic, ECG and tissue parameters were evaluated after banding to see the progression of CHF. The findings revealed that the constriction of the aorta above both renal arteries with 24 G needle is a better technique amongst other tested banding techniques as the rate of progression of CHF was found to be maximum with it. On the basis of above study, it was concluded that, aortic banding above both renal arteries with 24 G needle is a better technique for induction of pressure overload and for further observation in transition of the cardiac compensatory to decompensatory phase, the duration of the model needs to be prolonged.

Sex-Related Differences in Cardiac Remodeling and Reverse Remodeling After Transcatheter Aortic Valve Implantation in Patients with Severe Aortic Stenosis in a Japanese Population

Left ventricular (LV) remodeling with aortic stenosis (AS) appears to differ according to sex, but reverse remodeling after transcatheter aortic valve implantation (TAVI) has not been elucidated in a Japanese population. This study aims to determine whether any sex-related differences in LV or reverse remodeling after TAVI exist in the context of severe AS.Of 208 patients who received TAVI for severe AS in our institution, 100 (men, 42; mean age, 83.0 ± 4.9 years) underwent transthoracic echocardiography before and 3 months after TAVI. Despite similar valvular gradients, women with severe AS had lower indexed LV mass (LVMi) than did men (152.3 ± 35.4 versus 173.2 ± 44.6 g/m², P = 0.005), with smaller indexed LV end-diastolic (LVEDVi) (50.2 ± 13.3 versus 61.4 ± 20.7 mL/m², P = 0.001) and end-systolic (LVESVi; 17.9 ± 8.7 versus 24.3 ± 13.8 mL/m², P = 0.006) volumes. After TAVI, women (-6.0% ± 14.4%) had higher reduction in the rate of change of relative wall thickness (RWT) than did men (4.4% ± 19.0%, P = 0.003). Men (-8.9% ± 3.9%) had higher reduction in the rate of change of LVEDVi than did women (1.5% ± 3.3%, P = 0.045). Incidence of LV reverse remodeling defined as a reduction in LVESV of >15% was significantly higher in men (50%) than in women (26%, P = 0.013).In addition to sex differences in the pattern of LV remodeling with AS, reverse LV remodeling after TAVI also differed between sexes.

[Myocardial ischemia in patients with hypertrophic cardiomyopathy]

Authors present is comprehensive clinical and instrumental evaluation of patients with HCM with myocardial ischemia. 104 patients (38.4% of men) with HCM were examined, mean age 58.2±14.7. The examination included risk factors assessment for CAD, ECG, Echo, stress ECG test, 24-hour ECG monitoring. In the presence of myocardial ischemia, CAG (n=66) and MSCT of the coronary arteries (CA) (n=4) were performed. All patients were split up on 2 groups: I - 70 HCM patients with myocardial ischemia, 67.3%, and II (the control group) - 34 HCM patients without myocardial ischemia, 32.7%. The group I was divided on 2 subgroups: 1 - 29 patients with coronary atherosclerosis (41.4%), 2 - 41 patient without coronary atherosclerosis (58.6%). Age (p=0.046), family history (p=0.037), higher systolic and diastolic arterial pressure, long-term arterial hypertension (p<0.05) were determined as significant risk factors for CAD. Smaller diameter of LAD (p=0.008), higher LV mass index, greater LV diastolic function disorder (p<0.05) were detected in group 2 compared to group II. The decrease in myocardial perfusion (MBG scale) was associated with high LV mass index and cardiac arrhythmias. The frequency of concomitant coronary atherosclerosis among HCM patients with myocardial ischemia was determined as 41.4%. Analysis of traditional risk factors for CAD in patients with HCM revealed the strong relation to age, aggravated by a family history of CAD, blood pressure level and duration of hypertension. Smaller diameter of LAD, higher LV mass index, greater LV diastolic function disorder were observed in HCM patients with myocardial ischemia without CAD.

Impact of left ventricular remodelling patterns on outcomes in patients with aortic stenosis

Aims

The objective of this study was to examine the association between the different patterns of left ventricular (LV) remodelling/hypertrophy on all-cause and cardiovascular mortality in patients with aortic stenosis (AS).

Methods and results

In total, 747 consecutive patients (69 ± 14 years, 57% men) with AS and preserved LV ejection fraction were included in this study. According to LV mass index and relative wall thickness, patients were classified into four LV patterns: normal, concentric remodelling (CR), concentric hypertrophy (CH), and eccentric hypertrophy (EH). One hundred and sixteen patients (15%) had normal pattern, 66 (9%) had EH, 169 (23%) had CR, and 396 (53%) had CH. During a median follow-up of 6.4 years, 339 patients died (242 from cardiovascular causes). CH was associated with higher risk of all-cause mortality compared with the three other LV patterns (all P < 0.05). After multivariable adjustment, CH remained associated with higher risk of mortality (HR = 1.27, 95% CI 1.01-1.61, P = 0.046). There was a significant interaction (P < 0.05) between sex and CH with regards to the impact on mortality: CH was associated with worse outcome in women (P = 0.0001) but not in men (P = 0.22). In multivariable analysis, CH remained associated with higher risk of worse outcome in women (HR = 1.56, 95% CI 1.08-2.24, P = 0.018).

Conclusions

This study shows that CH was independently associated with increased risk of mortality in AS patients with preserved ejection fraction. This association was observed in women but not in men. The pattern of LV remodelling/hypertrophy should be integrated in the risk stratification process in patients with AS.

Myocardial Fibrosis in Competitive Triathletes Detected by Contrast-Enhanced CMR Correlates With Exercise-Induced Hypertension and Competition History

OBJECTIVES

This study analyzed the presence of myocardial fibrosis detected by late gadolinium-enhancement (LGE) cardiac magnetic resonance (CMR) in correlation with the performance of competitive triathletes objectified by an exercise test and individual competition history.

BACKGROUND

Myocardial fibrosis detected by LGE CMR has been reported to occur in 0% to 50% of asymptomatic athletes. However, the cause and mechanisms of myocardial fibrosis are unclear.

METHODS

Eighty-three asymptomatic triathletes undergoing >10 training h per week (43 ± 10 years of age; 65% male) and 36 sedentary controls were studied by using LGE and extracellular volume (ECV) CMR. Parameters of physical fitness were measured by spiroergometry. Triathletes reported their lifetime competition results.

RESULTS

LGE CMR revealed focal nonischemic myocardial fibrosis in 9 of 54 (17%) male triathletes (LGE⁺) but in none of the female triathletes (p < 0.05). LGE⁺ triathletes had higher peak exercise systolic blood pressure (213 ± 24 mm Hg) than LGE^- triathletes (194 ± 26 mm Hg; p < 0.05). Furthermore, left ventricular mass index was higher in LGE⁺ triathletes (93 ± 7 g/m²) than in LGE^- triathletes (84 ± 11 g/m²; p < 0.05). ECV in LGE^- myocardium was higher in LGE⁺ triathletes (26.3 ± 1.8%) than in LGE^- triathletes (24.4 ± 2.2%; p < 0.05). LGE⁺ triathletes completed longer cumulative distances in swimming and cycling races and participated more often in middle and Iron Man distances than LGE^- triathletes. A cycling race distance of >1,880 km completed during competition had the highest accuracy to predict LGE, with an area under the curve value of 0.876 (p < 0.0001), resulting in high sensitivity (89%) and specificity (79%). Multivariate analysis identified peak exercise systolic blood pressure (p < 0.05) and the swimming race distance (p < 0.01) as independent predictors of LGE presence.

CONCLUSIONS

Myocardial fibrosis in asymptomatic triathletes seems to be associated with exercise-induced hypertension and the race distances. There appears to be a safe upper limit, beyond which exercise may result in myocardial fibrosis.

Physical Activity Is Associated With Reduced Left Ventricular Mass in Obese and Hypertensive African Americans

BACKGROUND

Physical activity (PA) has been associated with decreased left ventricular (LV) hypertrophy in previous studies. However, little is known about the relationship between PA and LV structure and factors which influence this relationship among African Americans.

METHODS

We evaluated 1,300 African Americans with preserved LV ejection fraction (EF > 50%) from the Genetic Epidemiology Network of Arteriopathy (GENOA) Study (mean age 62.4 years, 73% women). PA index was calculated as 3 * heavy activity hours + 2 * moderate activity hours + slight activity hours/day. The relationship between PA index and LV structure was evaluated using generalized estimating equation. The association between PA index and LV mass index by age group, sex, body mass index (BMI), history of hypertension, diabetes or coronary heart disease, estimated glomerular filtration rate, and current smoking status were plotted.

RESULTS

After adjustment for these factors, higher PA index was independently associated with lower LV mass index (P < 0.05). There were significant interactions between PA index and obesity (BMI ≥ 30) and history of hypertension on LV mass index (P for interaction <0.05, for both). Higher PA index was associated with lower LV mass index more in obese or hypertensive participants compared with nonobese or nonhypertensive participants.

CONCLUSIONS

Higher PA index was associated with reduced LV hypertrophy in obese and hypertensive African Americans. Prospective studies aimed at assessing whether increasing PA prevents LV hypertrophy and potentially reduces the risk of heart failure in these at risk groups are warranted.

The association of metabolic syndrome with left ventricular mass and geometry in community-based hypertensive patients among Han Chinese

Background:

The association of metabolic syndrome (MS) with left ventricular (LV) hypertrophy is controversial. The objective of our study was to investigate the influence of MS on LV mass and geometry in community-based hypertensive patients among Han Chinese.

Materials and Methods:

This study included 1733 metabolic syndrome patients according to the International Diabetes Federation (IDF) definition and 2373 non-MS hypertension patients. LV hypertrophy was diagnosed by the criteria of LV mass ≥49.2 g/m^2.7 for men and 46.7 g/m^2.7 for women. LV geometric patterns (normal, concentric remodeling, concentric or eccentric hypertrophy) were calculated according to LV hypertrophy and relative wall thickness. Logistic regression analysis was used to determine odds ratio (OR) and 95% confidence interval (CI) of MS for LV hypertrophy and LV geometry abnormality.

Results:

The LV mass and LV mass index were higher in the MS group than in the non-MS group. In multiple adjusted models. LV mass index, LV mass, interventricular septum, and post wall were raised with the increased number of MS disorders. MS was associated with increased LV hypertrophy risk (unadjusted OR 1.38; 95% CI 1.21-1.57); age, sex, and blood pressure (BP; adjusted OR 1.39; 95% CI 1.22-1.59). MS was also associated with increased risk of eccentric hypertrophy in male and female patients. MS was only associated with increased risk of concentric hypertrophy in female patients; and MS was not associated with concentric remodeling.

Conclusion:

LV mass and LV mass index were associated with the increased number of MS disorders in the Chinese community-based hypertensive population. MS was not only associated with increased LV hypertrophy risk, but also associated with concentric and eccentric LV geometry abnormality, especially in females.

Hypertrophic cardiomyopathy: a review

Hypertrophic cardiomyopathy (HCM) is a global disease with cases reported in all continents, affecting people of both genders and of various racial and ethnic origins. Widely accepted as a monogenic disease caused by a mutation in 1 of 13 or more sarcomeric genes, HCM can present catastrophically with sudden cardiac death (SCD) or ventricular arrhythmias or insidiously with symptoms of heart failure. Given the velocity of progress in both the fields of heart failure and HCM, we present a review of the approach to patients with HCM, with particular attention to those with HCM and the clinical syndrome of heart failure.

Patterns of left ventricular diastolic function in Olympic athletes

BACKGROUND

Whether morphologic left ventricular (LV) changes in elite athletes are associated with altered diastolic properties is undefined. The aim of this study was to investigate LV diastolic properties in a large population of Olympic athletes compared to untrained controls.

METHODS

A total of 1,145 Olympic athletes (61% men), and 154 controls, free of cardiovascular disease, underwent two-dimensional echocardiography, Doppler echocardiography, and Doppler tissue imaging.

RESULTS

Athletes had similar E velocities (87 ± 15 vs 89 ± 16 cm/sec, P = .134) but significantly decreased A velocities (47 ± 10 vs 56 ± 12 cm/sec, P < .001) compared with controls, with increased E/A ratios (1.93 ± 0.50 vs 1.63 ± 0.35, P < .001) and values ranging up to 4.8. Isovolumic relaxation (83 ± 13 vs 71 ± 16 msec, P < .001) and deceleration times (203 ± 40 vs 181 ± 36 msec, P < .001) were longer in athletes compared with controls. Doppler tissue imaging e' (13.8 ± 2.2 vs 16.2 ± 3.7 cm/sec, P < .001) and a' (7.2 ± 1.8 vs 8.5 ± 2.1 cm/sec, P < .001) were lower in athletes than in controls, but their ratio was not different between groups; E/e' ratios (6.37 ± 1.2 vs 5.72 ± 1.33, P < .001) were mildly higher in athletes. Subgroup analysis for type of sport showed that endurance athletes had the lowest A and a' velocities and the largest E/A ratios. Gender analysis revealed that men had significantly lower E and A velocities, as well as e', e'/a' ratios, and E/e' ratios (P < .01), compared with women.

CONCLUSION

This study provides normal values for Doppler echocardiographic and Doppler tissue imaging parameters describing diastolic function in elite athletes, which may be implemented as reference values in the clinical assessment of athlete's heart and prove useful in understanding the physiologic limits of cardiac adaptations in athletes.

Benazepril inhibited the NF-κB and TGF-β networking on LV hypertrophy in rats

PURPOSE

Benazepril, an angiotensin-converting enzyme (ACE) inhibitor, has been used to treat hypertension, congestive heart failure, and chronic renal failure. However, its biological activity and mechanism of action in inflammation are not fully identified. The present study was designed to determine the in vivo anti-inflammatory effects of benazepril on LV hypertrophy in rats.

METHODS

LV hypertrophy was produced in rats by abdominal aortic coarctation. They were then divided into the following groups: sham operation; LV hypertrophy; LV hypertrophy+benazepril (1mg/kg in a gavage, once a day for 4 weeks). Both morphological assays (hemodynamic and hemorheological measurement; LV hypertrophy assessment), and molecular assays (protein levels of Collagen type I/III, TNF-α and VCAM-1; TGF-β gene expression; NF-κB or Smad activation; intracellular ROS production) were performed.

RESULTS

The following effects were observed in rats treated with benazepril: (1) marked improvements in hemodynamic and hemorheological parameters; (2) significant reductions in LV hypertrophy, dilatation and fibrosis; (3) significantly attenuated protein levels of Collagen type I/III, TGF-β, TNF-α and VCAM-1, NF-κB or Smad activation, as well as intracellular ROS production.

CONCLUSIONS

These results suggest that the anti-inflammatory properties of benazepril may be ascribed to their down-regulation of both NF-κB and TGF-β signaling pathways by acting on the intracellular ROS production in rats with LV hypertrophy, thus supporting the use of benazepril as an anti-inflammatory agent.

Long-term pattern of brain natriuretic peptide and N-terminal pro brain natriuretic peptide and its determinants in the general population: contribution of age, gender, and cardiac and extra-cardiac factors

AIMS

The natriuretic peptides BNP and NT-proBNP are potent cardiac markers, but knowledge of long-term changes is sparse. We thus quantified determinants of change in BNP and NT-proBNP in a study of south German residents (KORA).

METHODS AND RESULTS

A total of 1005 men and women (age 25-74 years, mean 48 years) underwent physical examination and echocardiography at baseline and at follow-up after 10 years. The current analysis comprised 877 subjects with dual measurements of BNP and NT-proBNP. Both markers increased in both sexes (P < 0.001) during the 10-year follow-up, and higher levels in women persisted across time (P for sex difference <0.001). Among baseline covariates, predictors for 10-year change of NT-proBNP, BNP, or both were age, sex, diabetes status, and heart rate (multivariable regression analysis, each P < 0.05). However, changes of covariates over the 10-year follow-up were much stronger determinants. Specifically, incident myocardial infarction, new beta-blocker medication, and increased cardiac parameters (left atrial diameter, LV end-diastolic diameter, and LV mass index) were associated with increasing BNP, NT-proBNP, or both, whereas increased heart rate, haematocrit, and body mass index (BMI) were associated with decreasing BNP and NT-proBNP (all P < 0.05).

CONCLUSION

Next to ageing and sex, a variety of changes in covariates reflecting the sequelae of cardiac remodelling as well as myocardial infarction and diabetes influence long-term changes of BNP and NT-proBNP. Of note, diabetes and increased BMI exert opposite effects. For interpretation of individual marker concentrations, a host of covariates needs to be considered, especially in subjects without prevalent or incident cardiac disease.