Patients with HFpEF have reduced cardiac energetic reserve that may underlie marked dynamic slowing of LV active relaxation and abnormal VVC during exercise.

BackgroundNonobstructive hypertrophic cardiomyopathy (nHCM) is often associated with reduced exercise capacity despite hyperdynamic systolic function as measured by left ventricular ejection fraction. We sought to examine the importance of left ventricular strain, twist, and untwist as predictors of exercise capacity in nHCM patients.MethodsFifty-six nHCM patients (31 male and mean age of 52 years) and 43 age- and gender-matched controls were enrolled. We measured peak oxygen consumption (peak Vo2) and acquired standard echocardiographic images in all participants. Two-dimensional speckle tracking was applied to measure rotation, twist, untwist rate, strain, and strain rate.ResultsThe nHCM patients exhibited marked exercise limitation compared with controls (peak Vo2 23.28 ± 6.31 vs 37.70 ± 7.99 mL/[kg min], P < .0001). Left ventricular ejection fraction in nHCM patients and controls was similar (62.76% ± 9.05% vs 62.48% ± 5.82%, P = .86). Longitudinal, radial, and circumferential strain and strain rate were all significantly reduced in nHCM patients compared with controls. There was a significant delay in 25% of untwist in nHCM compared with controls. Both systolic and diastolic apical rotation rates were lower in nHCM patients. Longitudinal systolic and diastolic strain rate correlated significantly with peak Vo2 (r = −0.34, P = .01 and r = 0.36, P = .006, respectively). Twenty-five percent untwist correlated significantly with peak Vo2 (r = 0.36, P = .006).ConclusionsIn nHCM patients, there are widespread abnormalities of both systolic and diastolic function. Reduced strain and delayed untwist contribute significantly to exercise limitation in nHCM patients.

Objective Left ventricular torsion is increased and cardiac energetics reduced in uncomplicated type 1 diabetes (T1DM). Our aim was to determine the relationships of these abnormalities to cardiovascular autonomic neuropathy (CAN) in subjects with T1DM. Materials/Methods A cross-sectional study was conducted in twenty subjects with T1DM free of known coronary heart disease attending an outpatient clinic. CAN was assessed using heart rate variability studies and the continuous wavelet transform method. Left ventricular function was determined by speckle tracking echocardiography. Magnetic resonance spectroscopy and stress magnetic resonance imaging was used to measure cardiac energetics and myocardial perfusion reserve index, respectively. Results Twenty subjects (age 35±8 years, diabetes duration 16±9 years, HbA1c 8.0±1.1%) were recruited. 40% subjects exhibited definite or borderline CAN. Log peak radial strain was significantly increased in subjects with CAN compared to those without (1.56±0.06 vs. 1.43±0.14 respectively, p=0.011). Data was adjusted for log duration of diabetes, and log left ventricular torsion correlated (r=0.593, p=0.01) with log low frequency-to-high frequency ratio during the Valsalva maneuver. Log isovolumic relaxation time correlated significantly with log Valsalva ratio and log pNN50 during deep breathing. However, CAN did not correlate with cardiac energetics or myocardial perfusion reserve index. Conclusions Spectral analysis of low frequency-to-high frequency ratio power during the Valsalva maneuver is associated with altered left ventricular torsion in subjects with T1DM. Parasympathetic dysfunction is closely associated with diastolic deficits. CAN is not however the principal cause of impaired cardiac energetics. The role of CAN in the development of cardiomyopathy warrants further evaluation.

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Summary A 62-year-old female was admitted with severe left-sided chest pain, nausea and pre-syncope. She had widespread T wave inversion on ECG and elevated troponins and was suspected to have an acute coronary syndrome event. Invasive coronary angiogram revealed normal coronary anatomy with no flow-limiting lesions. Echocardiography and cardiac MRI revealed impaired left ventricular (LV) systolic impairment, a mobile LV apical thrombus and a moderate global pericardial effusion with no significant compromise. Full blood count analysis indicated the patient to have significant eosinophilia, and the patient was diagnosed with idiopathic eosinophilic myocarditis. She was commenced on Prednisolone and Apixaban, and eosinophil levels returned to normal after 10 days of steroids. Over the course of 3 months, the patient had a complete recovery of her LV function and resolution of the LV thrombus. This case highlights a rare, reversible case of idiopathic eosinophilic myocarditis which may present similar to acute coronary syndrome. Learning points: Eosinophilic myocarditis (EM) is a rare disease that can exhibit symptoms similar to acute coronary syndrome events. The diagnosis of EM should be considered in patients with chest pain, normal coronary angiogram and pronounced eosinophilia levels. Endomyocardial biopsy is the gold standard diagnostic tool; however, it has a low sensitivity detection rate and its use is not indicated in some patients. Echocardiography is useful in the initial detection of cardiac involvement and complications. However, echocardiography lacks diagnostic specificity for all forms of myocarditis including EM. Cardiac magnetic resonance is a useful method and may add in diagnosing all forms of myocarditis including EM. Patients with EM should be identified promptly and treated with high doses of oral glucocorticoid to reduce the risk of permanent cardiac dysfunction.