Physical Activity, Inactivity and Sleep in Individuals with Hypertrophic Cardiomyopathy.

Physical activity presents an important cornerstone in the management and care of individuals with hypertrophic cardiomyopathy (HCM). Twenty-one individuals with HCM (age: 52±15 years old, body mass index (BMI): 30±7 kg/m2) completed 7-day monitoring using wrist-worn triaxial accelerometers (GENEActiv, ActivInsights Ltd, UK) and were compared to age and sex-matched healthy controls (age: 51±14 years old, BMI: 25±4 kg/m2). For individuals with HCM, clinical parameters (left atrial diameter and volume, peak oxygen consumption, NTproBNP and Minnesota Living with Heart Failure (MLHF)) were correlated with accelerometry. After adjusting for BMI, individuals with HCM spent less time in moderate-vigorous physical activity (MVPA) (86 (55-138) vs. 140 (121-149) minutes/day, p<0.05) compared to healthy controls. Individuals with HCM engaged in fewer MVPA-5 min (6 (2-15) vs. 27 (23-37) minutes/day, p<0.01) and MVPA-10 min bouts (9 (0-19) vs. 35 (17-54) minutes/day, p<0.01) versus healthy controls. For HCM only, peak oxygen consumption was correlated with MVPA (r=0.60, p<0.01) and MVPA-5 min bouts (r=0.47, p<0.05). MLHF score was correlated with sleep duration (r=0.45, p<0.05). Individuals with HCM should be encouraged to engage in moderate-intensity physical activity bouts and reduce prolonged periods of inactivity in order to potentially improve exercise tolerance and reduce disease burden.

Gender differences in the assessment, decision-making and outcomes for ventricular assist devices and heart transplantation: An analysis from a UK transplant center.

PURPOSE: There are marked gender differences in all etiologies of advanced heart failure. We sought to determine whether there is evidence of gender-specific decision making for transplant assessments, and how gender effects outcomes. METHODS: Retrospective analysis of adult heart transplant assessments at a single UK center between April 2015 and March 2020. RESULTS: Females were 32% of referrals (N = 137 females, 285 males), with marked differences between diagnoses - 11% ischemic and 43% of adult congenital. Females were younger, shorter, weighed less, and had lower pulmonary pressures. Females were much less likely to receive a ventricular assist device (13%). Blood type "O" females were relatively more likely compared to males to receive a transplant (45%). Comparing males and females who received a ventricular assist device, both had similar levels of high pulmonary pressures, indicating consistent decision-making based on hemodynamics to implant a device. Overall survival was better for females (in noncongenital patients), and this was due to female patients who were not accepted for transplant or a ventricular assist device being more often "too well for transplant," rather than in males when they were more often "unsuitable." CONCLUSIONS: Marked gender differences exist at all stages of the heart transplant assessment pathway. Appropriate decision-making based on clinical grounds is shown with less transplants in male blood type "O"s and hemodynamic criteria for ventricular assist device implantation in both genders. Further studies are needed to determine if there is a wider community bias in advanced heart failure treatments for females.

Haemodynamic determinants of quality of life in chronic heart failure.

BACKGROUND: Heart failure patients demonstrate reduced functional capacity, hemodynamic function, and quality of life (QOL) which are associated with high mortality and morbidity rate. The aim of the present study was to assess the relationship between functional capacity, hemodynamic response to exercise and QOL in chronic heart failure. METHODS: A single-centre prospective study recruited 42 chronic heart failure patients (11 females, mean age 60 ± 10 years) with reduced left ventricular ejection fraction (LVEF = 23 ± 7%). All participants completed a maximal graded cardiopulmonary exercise test with non-invasive hemodynamic (bioreactance) monitoring. QOL was assessed using Minnesota Living with Heart Failure Questionnaire. RESULTS: The average value of QOL score was 40 ± 23. There was a significant negative relationship between the QOL and peak O2 consumption (r = - 0.50, p ≤ 0.01). No significant relationship between the QOL and selected exercise hemodynamic measures was found, including peak exercise cardiac power output (r = 0.15, p = 0.34), cardiac output (r = 0.22, p = 0.15), and mean arterial blood pressure (r = - 0.08, p = 0.60). CONCLUSION: Peak O2 consumption, but not hemodynamic response to exercise, is a significant determinant of QOL in chronic heart failure patients.

Feasibility of the cardiac output response to stress test in suspected heart failure patients.

BACKGROUND: Diagnostic tools available to support general practitioners diagnose heart failure (HF) are limited. OBJECTIVES: (i) Determine the feasibility of the novel cardiac output response to stress (CORS) test in suspected HF patients, and (ii) Identify differences in the CORS results between (a) confirmed HF patients from non-HF patients, and (b) HF reduced (HFrEF) vs HF preserved (HFpEF) ejection fraction. METHODS: Single centre, prospective, observational, feasibility study. Consecutive patients with suspected HF (N = 105; mean age: 72 ± 10 years) were recruited from specialized HF diagnostic clinics in secondary care. The consultant cardiologist confirmed or refuted a HF diagnosis. The patient completed the CORS but the researcher administering the test was blinded from the diagnosis. The CORS assessed cardiac function (stroke volume index, SVI) noninvasively using the bioreactance technology at rest-supine, challenge-standing, and stress-step exercise phases. RESULTS: A total of 38 patients were newly diagnosed with HF (HFrEF, n = 21) with 79% being able to complete all phases of the CORS (91% of non-HF patients). A 17% lower SVI was found in HF compared with non-HF patients at rest-supine (43 ± 15 vs 51 ± 16 mL/beat/m2, P = 0.02) and stress-step exercise phase (49 ± 16 vs 58 ± 17 mL/beat/m2, P = 0.02). HFrEF patients demonstrated a lower SVI at rest (39 ± 15 vs 48 ± 13 mL/beat/m2, P = 0.02) and challenge-standing phase (34 ± 9 vs 42 ± 12 mL/beat/m2, P = 0.03) than HFpEF patients. CONCLUSION: The CORS is feasible and patients with HF responded differently to non-HF, and HFrEF from HFpEF. These findings provide further evidence for the potential use of the CORS to improve HF diagnostic and referral accuracy in primary care.

Heart failure (HF) is a global pandemic affecting 26 million people worldwide with an estimated 1 million people in the United Kingdom. Accurate early diagnosis of HF and the initiation of evidence-based treatment is essential to reduce morbidity and mortality and the associated burden on healthcare. As there are no state-of-the-art approaches, early diagnosis is challenging and often inaccurate, as initial signs and symptoms are nonspecific. We have developed an innovative test, named CORS (cardiac output response to stress test), to help general practitioners identify HF, which uses a method similar to an electrocardiogram and measures heart function at rest and during short step exercise. We recruited suspected HF patients from specialist HF diagnostic clinics in secondary care to complete the CORS test. We successfully demonstrated that 79% of patients with newly diagnosed HF (n = 38) and 91% of non-HF patients (n = 67) were able to complete all phases of the CORS test. Our findings demonstrate that newly diagnosed HF patients are able to complete this test, which provides further evidence for the potential use of the CORS test to improve HF diagnostic and referral accuracy in primary care.

Does infection predispose to thrombosis during long-term ventricular assist device support?

BACKGROUND: Infections and thrombotic events remain life-threatening complications in patients with ventricular assist devices (VAD). METHODS: We describe the relationship between both events in our cohort of patients (n = 220) supported with the HeartWare VAD (HVAD). This is a retrospective analysis of patients undergoing HVAD implantation between July 2009 and March 2019 at the Freeman Hospital, Newcastle upon Tyne, United Kingdom. RESULTS: Infection was the most common adverse event in HVAD patients, with 125 patients (56.8%) experiencing ≥ one infection (n = 168, 0.33 event per person year (EPPY)), followed by pump thrombosis (PT) in 61 patients (27.7%, 0.16 EPPY). VAD-specific infections were the largest group of infections. Of the 125 patients who had an infection, 66 (53%) had a thrombotic event. Both thrombotic events and infections were related to the duration of support, though there was only limited evidence that infections predispose to thrombosis. Those with higher than median levels of C-reactive protein during the infection were more likely to have an ischaemic stroke (IS) (34.5% vs 16.7%, p = .03), though not PT or a combined thrombotic event (CTE: first PT or IS). However, in multivariate analysis, there was no significant effect of infection predisposing to CTE. CONCLUSIONS: Infection and thrombotic events are significant adverse events related to the duration of support in patients receiving HVADs. Infections do not clearly predispose to thrombotic events.

Gender Related Differences in the Clinical Presentation of Hypertrophic Cardiomyopathy-An Analysis from the SILICOFCM Database.

Background and Objectives: Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiac disease that affects approximately 1 in 500 people. Due to an incomplete disease penetrance associated with numerous factors, HCM is not manifested in all carriers of genetic mutation. Although about two-thirds of patients are male, it seems that female gender is associated with more severe disease phenotype and worse prognosis. The objective of this study was to evaluate the gender related differences in HCM presentation. Materials and Methods: This study was conducted as a part of the international multidisciplinary SILICOFCM project. Clinical information, laboratory analyses, electrocardiography, echocardiography, and genetic testing data were collected for 362 HCM patients from four clinical centers (Florence, Newcastle, Novi Sad, and Regensburg). There were 33% female patients, and 67% male patients. Results: Female patients were older than males (64.5 vs. 53.5 years, p < 0.0005). The male predominance was present across all age groups until the age of 70, when gender distribution became comparable. Females had higher number of symptomatic individuals then males (69% vs. 52%, p = 0.003), most frequently complaining of dyspnea (50% vs. 30%), followed by chest pain (30% vs. 17%), fatigue (26% vs. 13%), palpitations (22% vs. 13%), and syncope (13% vs. 8%). The most common rhythm disorder was atrial fibrillation which was present in a similar number of females and males (19% vs. 13%, p = 0.218). Levels of N-terminal pro-brain natriuretic peptide were comparable between the genders (571 vs. 794 ng/L, p = 0.244). Echocardiography showed similar thickness of interventricular septum (18 vs. 16 mm, p = 0.121) and posterolateral wall (13 vs. 12 mm, p = 0.656), however, females had a lower number of systolic anterior motion (8% vs. 16%, p = 0.020) and other mitral valve abnormalities. Conclusions: Female patients are underrepresented but seem to have a more pronounced clinical presentation of HCM. Therefore, establishing gender specific diagnostic criteria for HCM should be considered.

Validity of Hemodynamic Monitoring Using Inert Gas Rebreathing Method in Patients With Chronic Heart Failure and Those Implanted With a Left Ventricular Assist Device.

OBJECTIVE: The present study assessed agreement between resting cardiac output estimated by inert gas rebreathing (IGR) and thermodilution methods in patients with heart failure and those implanted with a left ventricular assist device (LVAD). METHODS AND RESULTS: Hemodynamic measurements were obtained in 42 patients, 22 with chronic heart failure and 20 with implanted continuous flow LVAD (34 males, aged 50 ± 11 years). Measurements were performed at rest using thermodilution and IGR methods. Cardiac output derived by thermodilution and IGR were not significantly different in LVAD (4.4 ± 0.9 L/min vs 4.7 ± 0.8 L/min, P = .27) or patients with heart failure (4.4 ± 1.4 L/min vs 4.5 ± 1.3 L/min, P = .75). There was a strong relationship between thermodilution and IGR cardiac index (r = 0.81, P = .001) and stroke volume index (r = 0.75, P = .001). Bland-Altman analysis showed acceptable limits of agreement for cardiac index derived by thermodilution and IGR, namely, the mean difference (lower and upper limits of agreement) for patients with heart failure -0.002 L/min/m2 (-0.65 to 0.66 L/min/m2), and -0.14 L/min/m2 (-0.78 to 0.49 L/min/m2) for patients with LVAD. CONCLUSIONS: IGR is a valid method for estimating cardiac output and should be used in clinical practice to complement the evaluation and management of chronic heart failure and patients with an LVAD.

Noninvasive Assessment of Cardiac Output in Advanced Heart Failure and Heart Transplant Candidates Using the Bioreactance Method.

OBJECTIVES: The aim of the present study was to assess the validity and trending ability of the bioreactance method in estimating cardiac output at rest and in response to stress in advanced heart failure patients and heart transplant candidates. DESIGN: This was a prospective single-center study. SETTING: This study was conducted at the heart transplant center at the Freeman Hospital, Newcastle upon Tyne, UK. PARTICIPANTS: Eighteen patients with advanced chronic heart failure due to reduced left ventricular ejection fraction (19 ± 7%), and peak oxygen consumption 12.3 ± 3.9 mL/kg/min. INTERVENTIONS: Participants underwent right heart catheterization using the Swan-Ganz catheter. MEASUREMENTS AND MAIN RESULTS: Cardiac output was measured simultaneously using thermodilution and bioreactance at rest and during active straight leg raise test to volitional exertion. There was no significant difference in cardiac index values obtained by the thermodilution and bioreactance methods (2.26 ± 0.59 v 2.38 ± 0.50 L/min, p > 0.05) at rest and peak straight leg raise test (2.92 ± 0.77 v 3.01 ± 0.66 L/min, p > 0.05). In response to active leg raise test, thermodilution cardiac output increased by 22% and bioreactance by 21%. There was also a strong relationship between cardiac outputs from both methods at rest (r = 0.88, p < 0.01) and peak straight leg raise test (r = 0.92, p < 0.01). Cartesian plot analysis showed good trending ability of bioreactance compared with thermodilution (concordance rate = 93%) CONCLUSIONS: `Cardiac output measured by the bioreactance method is comparable to that from the thermodilution method. Bioreactance method may be used in clinical practice to assess hemodynamics and improve management of advanced heart failure patients undergoing heart transplant assessment.

Genetic determinants of clinical phenotype in hypertrophic cardiomyopathy.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiovascular disease that affects approximately one in 500 people. HCM is a recognized genetic disorder most often caused by mutations involving myosin-binding protein C (MYBPC3) and ß-myosin heavy chain (MYH7) which are responsible for approximately three-quarters of the identified mutations. METHODS: As a part of the international multidisciplinary SILICOFCM project ( www.silicofcm.eu ) the present study evaluated the association between underlying genetic mutations and clinical phenotype in patients with HCM. Only patients with confirmed single pathogenic mutations in either MYBPC3 or MYH7 genes were included in the study and divided into two groups accordingly. The MYBPC3 group was comprised of 48 patients (76%), while the MYH7 group included 15 patients (24%). Each patient underwent clinical examination and echocardiography. RESULTS: The most prevalent symptom in patients with MYBPC3 was dyspnea (44%), whereas in patients with MYH7 it was palpitations (33%). The MYBPC3 group had a significantly higher number of patients with a positive family history of HCM (46% vs. 7%; p = 0.014). There was a numerically higher prevalence of atrial fibrillation in the MYH7 group (60% vs. 35%, p = 0.085). Laboratory analyses revealed normal levels of creatinine (85.5 ± 18.3 vs. 81.3 ± 16.4 µmol/l; p = 0.487) and blood urea nitrogen (10.2 ± 15.6 vs. 6.9 ± 3.9 mmol/l; p = 0.472) which were similar in both groups. The systolic anterior motion presence was significantly more frequent in patients carrying MYH7 mutation (33% vs. 10%; p = 0.025), as well as mitral leaflet abnormalities (40% vs. 19%; p = 0.039). Calcifications of mitral annulus were registered only in MYH7 patients (20% vs. 0%; p = 0.001). The difference in diastolic function, i.e. E/e' ratio between the two groups was also noted (MYBPC3 8.8 ± 3.3, MYH7 13.9 ± 6.9, p = 0.079). CONCLUSIONS: Major findings of the present study corroborate the notion that MYH7 gene mutation patients are presented with more pronounced disease severity than those with MYBPC3.

Comparison of cardiac output estimates by echocardiography and bioreactance at rest and peak dobutamine stress test in heart failure patients with preserved ejection fraction.

PURPOSE: To assess the agreement between cardiac output estimated by two-dimensional echocardiography and bioreactance methods at rest and during dobutamine stress test in heart failure patients with preserved left ventricular ejection fraction (HFpEF). METHODS: Hemodynamic measurements were assessed in 20 stable HFpEF patients (12 females; aged 61 ± 7 years) using echocardiography and bioreactance methods during rest and dobutamine stress test at increment dosages of 5, 10, 15, and 20 µg/kg/min until maximal dose was achieved or symptoms and sign occurred, that is, chest pain, abnormal blood pressure elevation, breathlessness, ischemic changes, or arrhythmia. RESULTS: Resting cardiac output and cardiac index estimated by bioreactance and echocardiography were not significantly different. At peak dobutamine stress test, cardiac output and cardiac index estimated by echocardiography and bioreactance were significantly different (7.06 ± 1.43 vs 5.71 ± 1.59 L/min, P < .01; and 4.27 ± 0.67 vs 3.43 ± 0.87 L/m2 /min; P < .01) due to the significant differences in stroke volume. There was a strong positive relationship between cardiac outputs obtained by the two methods at peak dobutamine stress (r = .79, P < .01). The mean difference (lower and upper limits of agreement) between bioreactance and echocardiography cardiac outputs at rest and peak dobutamine stress was -0.45 (1.71 to -2.62) L/min and -1.35 (0.60 to -3.31) L/min, respectively. CONCLUSION: Bioreactance and echocardiography methods provide different cardiac output values at rest and during stress thus cannot be used interchangeably. Ability to continuously monitor key hemodynamic variables such as cardiac output, stroke volume, and heart rate is the major advantage of bioreactance method.

Effects of drug abuse, smoking and alcohol on donor hearts and lungs.

Potential heart and lung donors with a history of illicit drugs and/or smoking and alcohol are frequently offered, though there is no clear guidance on when it is safe to use these organs. A review of the literature on effects of drugs, alcohol and smoking on donor outcomes, and the effects of these on the intact heart and lung was undertaken. There has been a marked increase in deaths from opioid abuse in many developed countries, though recent evidence suggests that outcomes after cardiothoracic transplantation are equivalent to nonopioid donor causes of death. For donor smoking, there is an increased risk with lung transplantation; however, that risk is less when compared to further waiting on the transplant list for a nonsmoking alternative. Heavy alcohol consumption does not adversely affect heart transplantation, and there is no clear evidence of adverse outcomes after lung transplantation. There are no overall effects of cannabis or cocaine on survival after heart or lung transplantation. In all these cases, careful donor assessment can establish if a particular organ can be used. In most cases, use of drugs requires careful assessment, but is not in of itself a contraindication to cardiothoracic transplantation.

Association between heart rate variability and haemodynamic response to exercise in chronic heart failure.

OBJECTIVES: Heart rate variability (HRV) and haemodynamic response to exercise (i.e. peak cardiac power output) are strong predictors of mortality in heart failure. The present study assessed the relationship between measures of HRV and peak cardiac power output. DESIGN: In a prospective observational study of 33 patients (age 54 ± 16 years) with chronic heart failure with reduced left ventricular ejection fraction (29 ± 11%), measures of the HRV (i.e. R-R interval and standard deviation of normal R-R intervals, SDNN) were recorded in a supine position. All patients underwent maximal graded cardiopulmonary exercise testing with non-invasive (inert gas rebreathing) cardiac output assessment. Cardiac power output, expressed in watts, was calculated as the product of cardiac output and mean arterial blood pressure. RESULTS: The mean RR and SDNN were 837 ± 166 and 96 ± 29 ms, peak exercise cardiac power output 2.28 ± 0.85 watts, cardiac output 10.34 ± 3.14 L/min, mean arterial blood pressure 98 ± 14 mmHg, stroke volume 91.43 ± 40.77 mL/beat, and oxygen consumption 19.0 ± 5.6 mL/kg/min. There was a significant but only moderate relationship between the RR interval and peak exercise cardiac power output (r = 0.43, p = .013), cardiac output (r = 0.35, p = .047), and mean arterial blood pressure (r = 0.45, p = .009). The SDNN correlated with peak cardiac power output (r = 0.42, p = .016), mean arterial blood arterial (r = 0.41, p = .019), and stroke volume (r = 0.35, p = .043). CONCLUSIONS: Moderate strength of the relationship between measures of HRV and cardiac response to exercise suggests that cardiac autonomic function is not good indicator of overall function and pumping capability of the heart in chronic heart failure.

Pregnancy in cardiac transplant recipients.

PURPOSE: Successful pregnancy following cardiac transplantation has been described, although outcome data from individual centers are relatively sparse. We investigated maternal and fetal outcomes including change in left ventricular (LV) function and calcineurin inhibitor (CNI) dose in women who became pregnant from our institution. METHODS: We identified every female patient <49 years at the time of transplant who survived >3 months post-surgery, between 1985 and 2014. Those who conceived had a review of their medical records and transplant charts. Those currently alive were interviewed. RESULTS: There were 22 pregnancies in 17 women with 20 live births (91%). Mean time from transplantation was 98±62.4 months. Rejection complicated one pregnancy, and LV function remained normal in all others. Hypertension complicated 3 (13.6%), preeclampsia 3 (13.6%), and cholestasis 1 (4.5%). Mean birthweight was 2447±608 grams at 34.1±3.6 weeks. Four women died following pregnancy. A significant increase in total daily dose of tacrolimus and cyclosporine A was required to maintain therapeutic levels through pregnancy (CyA, P<.001; and Tac, P=.001), with no deterioration in serum creatinine. CONCLUSIONS: We report a 91% live birth rate post-cardiac transplantation. Meticulous individualized care with frequent monitoring of CNI levels and LV function is necessary to optimize the maternal and fetal outcomes.

Measurement of pulse wave velocity in normal ageing: comparison of Vicorder and magnetic resonance phase contrast imaging.

BACKGROUND: Pulse wave velocity is an important measure of cardiovascular risk, and can be measured by several different techniques. We compared age-related changes in pulse wave velocity derived from carotid and femoral artery waveforms using the Vicorder device and descending thoracic aorta time velocity curves using phase contrast magnetic resonance imaging (MRI) in a group of normal healthy volunteers, without cardiovascular disease, aged between 20 and 79 years. METHODS: Eighty subjects underwent same-day measurements of Vicorder and MRI pulse wave velocity measurements. RESULTS: Both Vicorder and MRI-based pulse wave velocity measurements were significantly increased with age (R = 0.59 and 0.57 respectively, both P < 0.0001). Vicorder and MRI pulse wave velocities were also significantly related to each other (R = 0.27, P < 0.05), and Bland Altman plots showed that on average Vicorder measurements were 1.6 m/s greater than MRI. In 5% of cases, agreement between the values of the two techniques were above and below 2 standard deviations, and these were at higher levels of pulse wave velocities. Multiple linear stepwise regression analysis confirmed highly significant relationships of both techniques to age (both P < 0.0001), and MRI was also significantly related to heart rate (P = 0.006) but Vicorder was not. CONCLUSIONS: Both Vicorder and MRI perform similarly in detecting age-related changes in pulse wave velocity. Thus, the choice of using one or the other will depend on other aspects of the investigation, such as the need for portability favouring Vicorder, or need for additional cardiovascular imaging favouring MRI. TRIAL REGISTRATION: ClinicalTrials.Gov identifier NCT01504828.

Cardiac structure and function are altered in type 2 diabetes and non-alcoholic fatty liver disease and associate with glycemic control.

BACKGROUND: Both non-alcoholic fatty liver disease (NAFLD) and Type 2 diabetes increase the risk of developing cardiovascular disease. The metabolic processes underlying NAFLD and Type 2 diabetes are part of an integrated mechanism but little is known about how these conditions may differentially affect the heart. We compared the impact of NAFLD and Type 2 diabetes on cardiac structure, function and metabolism. METHODS: 19 adults with Type 2 diabetes (62 ± 8 years), 19 adults with NAFLD (54 ± 15 years) and 19 healthy controls (56 ± 14 years) underwent assessment of cardiac structure, function and metabolism using high resolution magnetic resonance imaging, tagging and spectroscopy at 3.0 T. RESULTS: Adults with NAFLD and Type 2 diabetes demonstrate concentric remodelling with an elevated eccentricity ratio compared to controls (1.05 ± 0.3 vs. 1.12 ± 0.2 vs. 0.89 ± 0.2 g/ml; p < 0.05). Despite this, only the Type 2 diabetes group demonstrate significant systolic and diastolic dysfunction evidenced by a reduced stroke index (31 ± 7vs. controls, 38 ± 10, p < 0.05 ml/m2) and reduced E/A (0.9 ± 0.4 vs. controls, 1.9 ± 1.4, p < 0.05) respectively. The torsion to shortening ratio was higher in Type 2 diabetes compared to NAFLD (0.58 ± 0.16 vs. 0.44 ± 0.13; p < 0.05). Significant associations were observed between fasting blood glucose/HbA1c and diastolic parameters as well as the torsion to shortening ratio (all p < 0.05). Phosphocreatine/adenosine triphosphate ratio was not altered in NAFLD or Type 2 diabetes compared to controls. CONCLUSIONS: Changes in cardiac structure are evident in adults with Type 2 diabetes and NAFLD without overt cardiac disease and without changes in cardiac energy metabolism. Only the Type 2 diabetes group display diastolic and subendocardial dysfunction and glycemic control may be a key mediator of these cardiac changes. Therapies should be explored to target these preclinical cardiac changes to modify cardiovascular risk associated with Type 2 diabetes and NAFLD.

Sacubitril/valsartan for the treatment of non-obstructive hypertrophic cardiomyopathy: An open label randomized controlled trial (SILICOFCM).

AIM: Sacubitril/valsartan treatment reduces mortality and hospitalizations in heart failure with reduced ejection fraction but has limited application in hypertrophic cardiomyopathy (HCM). The aim of this study was to evaluate the effect of sacubitril/valsartan on peak oxygen consumption (VO2) in patients with non-obstructive HCM. METHODS AND RESULTS: This is a phase II, randomized, open-label multicentre study that enrolled adult patients with symptomatic non-obstructive HCM (New York Heart Association class I-III) who were randomly assigned (2:1) to receive sacubitril/valsartan (target dose 97/103 mg) or control for 16 weeks. The primary endpoint was a change in peak VO2. Secondary endpoints included echocardiographic measures of cardiac structure and function, natriuretic peptides and other cardiac biomarkers, and Minnesota Living with Heart Failure quality of life. Between May 2018 and October 2021, 354 patients were screened for eligibility, 115 patients (mean age 58 years, 37% female) met the study inclusion criteria and were randomly assigned to sacubitril/valsartan (n = 79) or control (n = 36). At 16 weeks, there was no significant change in peak VO2 from baseline in the sacubitril/valsartan (15.3 [4.3] vs. 15.9 [4.3] ml/kg/min, p = 0.13) or control group (p = 0.47). No clinically significant changes were found in blood pressure, cardiac structure and function, plasma biomarkers, or quality of life. CONCLUSION: In patients with HCM, a 16-week treatment with sacubitril/valsartan was well tolerated but had no effect on exercise capacity, cardiac structure, or function.

Cardiac structure and function are altered in adults with non-alcoholic fatty liver disease.

BACKGROUND & AIMS: Non-alcoholic fatty liver disease (NAFLD) is associated with a twofold greater risk of developing cardiovascular disease. Despite this, little is known about the effect of NAFLD upon cardiac function, limiting our ability to identify therapeutic strategies. This study aimed to address this by defining the effect of NAFLD on cardiac function, structure, and metabolism. METHODS: Nineteen adults with NAFLD were age-, sex-, and BMI-matched to healthy controls without liver or metabolic disease. Cardiac structure and function were assessed using high-resolution cardiac MRI and tagging at 3.0 T. High-energy phosphate metabolism was assessed using (31)P-magnetic resonance spectroscopy to measure the PCr/ATP ratio. RESULTS: Adults with NAFLD had significantly thicker left ventricular walls at systole (14 ± 3 vs. 12 ± 2 mm; p <0.01) and diastole (8 ± 1 vs. 7 ± 1 mm; p <0.01) than those without fatty liver and showed decreased longitudinal shortening (14 ± 3 vs. 17 ± 3%; p <0.01). The eccentricity ratio was significantly higher in the NAFLD group (1.1 ± 0.2 vs. 0.9 ± 0.2 g/ml; p <0.01) indicating concentric remodelling. Peak whole wall strain was higher in the NAFLD group (19 ± 2 vs. 17 ± 3%; p <0.01), as was peak endocardial strain (28 ± 4 vs. 22 ± 5%; p <0.01). Cardiac metabolism, measured by PCr/ATP ratio, was not altered in NAFLD (1.8 ± 0.3 vs. 1.9 ± 0.3; p=0.36). CONCLUSIONS: Significant changes in cardiac structure and function are evident in adults with NAFLD in the apparent absence of metabolic changes or overt cardiac disease. Clinicians should continue to explore therapies to improve cardiac function as a means to modify the excess risk of cardiovascular disease associated with NAFLD.

Heterogeneous abnormalities of in-vivo left ventricular calcium influx and function in mouse models of muscular dystrophy cardiomyopathy.

BACKGROUND: Manganese-enhanced cardiovascular magnetic resonance (MECMR) can non-invasively assess myocardial calcium influx, and calcium levels are known to be elevated in muscular dystrophy cardiomyopathy based on cellular studies. METHODS: Left ventricular functional studies and MECMR were performed in mdx mice (model of Duchenne muscular dystrophy, 24 and 40 weeks) and Sgcd -/- mice (limb girdle muscular dystrophy 2 F, 16 and 32 weeks), compared to wild type controls (C57Bl/10, WT). RESULTS: Both models had left ventricular hypertrophy at the later age compared to WT, though the mdx mice had reduced stroke volumes and the Sgcd -/- mice increased heart rate and cardiac index. Especially at the younger ages, MECMR was significantly elevated in both models (both P < 0.05 versus WT). The L-type calcium channel inhibitor diltiazem (5 mg/kg i.p.) significantly reduced MECMR in the mdx mice (P < 0.01), though only with a higher dose (10 mg/kg i.p.) in the Sgcd -/- mice (P < 0.05). As the Sgcd -/- mice had increased heart rates, to determine the role of heart rate in MECMR we studied the hyperpolarization-activated cyclic nucleotide-gated channel inhibitor ZD 7288 which selectively reduces heart rate. This reduced heart rate and MECMR in all mouse groups. However, when looking at the time course of reduction of MECMR in the Sgcd -/- mice at up to 5 minutes of the manganese infusion when heart rates were matched to the WT mice, MECMR was still significantly elevated in the Sgcd -/- mice (P < 0.01) indicating that heart rate alone could not account for all the increased MECMR. CONCLUSIONS: Despite both mouse models exhibiting increased in-vivo calcium influx at an early stage in the development of the cardiomyopathy before left ventricular hypertrophy, there are distinct phenotypical differences between the 2 models in terms of heart rates, hemodynamics and responses to calcium channel inhibitors.