Myocarditis is an inflammatory disease of the myocardium, and its diagnosis remains challenging owing to a varying clinical presentation and broad spectrum of underlying aetiologies. In clinical practice, cardiovascular magnetic resonance has become an invaluable non-invasive imaging tool in the evaluation of patients with clinically suspected myocarditis, mainly thanks to its unique multiparametric tissue characterization ability. Although considered as useful, the method also has its limitations. This review aims to provide an up-to-date overview of the strengths and weaknesses of cardiovascular magnetic resonance in the diagnostic work-up of patients with clinically suspected myocarditis in a broad clinical context.
Sympathetic nerve activity is increased in hypertensive patients with renal artery stenosis. Less is known about cardiac vagal function in these patients before and after renal angioplasty. The aim of the present study was to investigate cardiac baroreceptor reflex sensitivity together with total body noradrenaline (NA) spillover in hypertensive patients with renal artery stenosis before, and in some patients, 1 year after renal angioplasty. Spontaneous baroreceptor reflex sensitivity and total body noradrenaline (NA) spillover were measured in patients with renovascular hypertension before intervention (n = 18), patients being cured/improved 1 year after renal angioplasty (n = 5) and age-matched healthy subjects (n = 25). Hypertensive patients with renal artery stenosis had higher total body NA spillover (4630 ± 619 versus 3132 ± 210 pmol/min, P < 0.05) and reduced cardiac baroreceptor reflex sensitivity (6.1 ± 1.0 versus 10.7 ± 1.0 ms/mmHg, P < 0.01) compared with healthy subjects. Similar results were obtained (before intervention) in a subgroup of patients (n = 9) with renovascular hypertension defined as cured/improved 1 year following renal angioplasty. Baroreceptor reflex sensitivity improved after renal angioplasty in a subset of patients showing good blood pressure control 1 year after intervention (6.4 ± 0.7 to 9.4 ± 1.7 ms/mmHg, P < 0.05). Patients with renovascular hypertension showed reduced cardiac baroreceptor reflex sensitivity and increased noradrenergic activity, which to some extent was reversed 1 year following successful renal angioplasty.
Echocardiographic evaluation of chronic aortic regurgitation (AR) severity can lead to diagnostic ambiguity due to few feasible parameters or incongruent findings. The aim of the present study was to improve the diagnostic usefulness of left ventricular (LV) enlargement and aortic end-diastolic flow velocity (EDFV) using cardiovascular magnetic resonance (CMR) as reference. Patients (n = 120) were recruited either prospectively (n = 45) or retrospectively (n = 75). Severe AR (CMR regurgitant fraction 75/87 ml/m2) were identified using ROC analyses in the derivation group. The corresponding thresholds for EDFV were 10 cm/s. In the test group, the positive/negative likelihood ratios to rule in/rule out severe AR using EDVI were 10.0/0.14 (traditional), 6.2/0.11 (recommended), and using EDFV were 10.2/0.08. To rule in and rule out severe AR using derived cut-off values instead of 2 SD reduced the false positives by 92%, whereas using EDFV <10 cm/s instead of <20 cm/s reduced the false negatives by 94%. In conclusion, EDVI and EDFV as quantitative parameters are useful to rule in or rule out severe chronic AR. Importantly, other causes of LV enlargement have to be considered.