Clinical Presentation and Outcome in a Contemporary Cohort of Patients With Acute Myocarditis: Multicenter Lombardy Registry.

BACKGROUND: There is controversy about the outcome of patients with acute myocarditis (AM), and data are lacking on how patients admitted with suspected AM are managed. We report characteristics, in-hospital management, and long-term outcome of patients with AM based on a retrospective multicenter registry from 19 Italian hospitals. METHODS: A total of 684 patients with suspected AM and recent onset of symptoms (<30 days) were screened between May 2001 and February 2017. Patients >70 years of age and those >50 years of age without coronary angiography were excluded. The final study population comprised 443 patients (median age, 34 years; 19.4% female) with AM diagnosed by either endomyocardial biopsy or increased troponin plus edema and late gadolinium enhancement at cardiac magnetic resonance. RESULTS: At presentation, 118 patients (26.6%) had left ventricular ejection fraction <50%, sustained ventricular arrhythmias, or a low cardiac output syndrome, whereas 325 (73.4%) had no such complications. Endomyocardial biopsy was performed in 56 of 443 (12.6%), and a baseline cardiac magnetic resonance was performed in 415 of 443 (93.7%). Cardiac mortality plus heart transplantation rates at 1 and 5 years were 3.0% and 4.1%. Cardiac mortality plus heart transplantation rates were 11.3% and 14.7% in patients with complicated presentation and 0% in uncomplicated cases (log-rank P<0.0001). Major AM-related cardiac events after the acute phase (postdischarge death and heart transplantation, sustained ventricular arrhythmias treated with electric shock or ablation, symptomatic heart failure needing device implantation) occurred in 2.8% at the 5-year follow-up, with a higher incidence in patients with complicated forms (10.8% versus 0% in uncomplicated AM; log-rank P<0.0001). ß-Adrenoceptor blockers were the most frequently used medications both in complicated (61.9%) and in uncomplicated forms (53.8%; P=0.18). After a median time of 196 days, 200 patients had follow-up cardiac magnetic resonance, and 8 of 55 (14.5%) with complications at presentation had left ventricular ejection fraction <50% compared with 1 of 145 (0.7%) of those with uncomplicated presentation. CONCLUSIONS: In this contemporary study, overall serious adverse events after AM were lower than previously reported. However, patients with left ventricular ejection fraction <50%, ventricular arrhythmias, or low cardiac output syndrome at presentation were at higher risk compared with uncomplicated cases that had a benign prognosis and low risk of subsequent left ventricular systolic dysfunction.

Transthoracic Doppler ultrasound coronary flow reserve evaluation: preliminary insights into pathophysiology of Takotsubo cardiomyopathy.

OBJECTIVE: The aim of this study was to elucidate the role of coronary microvascular function in the pathophysiological scenario of Takotsubo cardiomyopathy. METHODS: Noninvasive evaluations of coronary flow reserve through transthoracic Doppler ultrasound imaging of the left anterior descending coronary artery, a reliable marker of coronary microcirculation performance in the absence of epicardial coronary artery stenosis, were performed both in the acute and recovery phases of Takotsubo cardiomyopathy in consecutive patients strictly selected on the basis of absence of risk factors, concomitant diseases, or both impairing coronary microvascular function. RESULTS: Resting and hyperemic diastolic flow velocity tracings and corresponding velocity time integrals were obtained in seven consecutive patients, six of them women, aged 65-86 years (76 +/- 6.5) at admission and 23 +/- 4 days after, when left ventricular wall motion alterations recovered. In addiction, thrombolysis in myocardial infarction frame count of the two branches of the left coronary artery was evaluated on the cineangiogram obtained at admission. It was normal in both branches of the left coronary artery (left anterior descending, 30.6 +/- 8.79; circumflex, 23.4 +/- 2.96). In each patient, coronary flow reserve, calculated both on velocity time integrals (2.6 +/- 0.2) and average peak diastolic blood flow velocity (2.48 +/- 0.1) values, was in the normal range (>2.0) and did not significantly change when reevaluated in the recovery phase (2.55 +/- 0.1, 2.44 +/- 0.1). CONCLUSION: These data suggest that coronary microvascular function may not be impaired in Takotsubo patients when negative influences on coronary flow reserve by concomitant diseases and coronary risk factors are excluded. Its noninvasive evaluation with transthoracic Doppler ultrasound of the distal left anterior descending appears simple and useful in this type of patients.