Establishing the diagnosis of inverted stress cardiomyopathy in a patient with cardiac arrest during general anesthesia: a potential role of myocardial strain?

In cardiac arrest survivors, postresuscitation myocardial stunning usually presents as either global left ventricular dysfunction or regional dyssynergy including the various forms of stress cardiomyopathy, in which rare variants may be difficult to diagnose. We present a patient with cardiac arrest during general anesthesia, in whom speckle tracking-derived myocardial strain helped to distinguish between the inverted variant of stress cardiomyopathy and global postresuscitation myocardial stunning.

Prognostic significance of contractile reserve assessed by dobutamine-induced changes of Tei index in patients with idiopathic dilated cardiomyopathy.

AIMS: To determine prognostic significance of global left ventricular (LV) contractile reserve, defined by dobutamine-induced changes of Tei index (Delta Tei), in patients with dilated cardiomyopathy (DCM). METHODS AND RESULTS: Thirty-eight patients with idiopathic DCM underwent high-dose (up to 40 microg/kg/min) dobutamine stress echocardiography. Prognostic value of different indices of LV contractile reserve, including Delta Tei, as well as changes of ejection fraction (Delta EF) and wall motion score index (Delta WMSi), was analysed. Patients were followed up for 5 years for cardiac mortality. Patients with preserved contractile reserve, defined by Delta Tei > -0.35, had significantly lower cardiac mortality when compared with those without it (38 vs. 77%, P = 0.02). Also, the Kaplan-Meier survival analysis revealed that patients with contractile reserve had better 5-year survival when compared with those without contractile reserve (log-rank = 6.01, P = 0.014). However, of all examined indices of contractile reserve, Cox's regression analysis identified Delta WMSi as the only independent predictor of 5-year mortality. CONCLUSION: Our data indicate that the presence of contractile reserve assessed by Delta Tei may identify patients with favourable long-term prognosis. Prognostic value of Delta Tei appears to be similar to Delta EF, but less powerful than Delta WMSi.

Effect of myocardial revascularisation on left ventricular systolic function in patients with and without viable myocardium: should non-viable segments be revascularised?

OBJECTIVE: To assess the effect of surgical revascularisation on left ventricular (LV) systolic function in patients with viable and non-viable dysfunctional LV segments determined by low dose dobutamine stress echocardiography (DSE). DESIGN: Prospective observational cohort study. SETTING: Single tertiary care centre. PATIENTS: Consecutive patients referred to surgical revascularisation (n=115). INTERVENTIONS: DSE and surgical revascularisation. MAIN OUTCOME MEASURES: Functional recovery defined as increase in ejection fraction ≥ 5% 1 year after revascularisation in patients with and without viable myocardium (viability defined as improvement of contractility in ≥ 4 LV segments on DSE). RESULTS: The mean age, ejection fraction and wall motion score index (WMSi) of patients were 59 ± 9 years, 44 ± 9% and 1.82 ± 0.31, respectively. There was no difference between DSE positive and DSE negative patients for any of those parameters at baseline study (p>0.05 for all). After 12 months, the ejection fraction increased 11 ± 1% in patients with viable myocardium vs 7 ± 1% in patients without viable myocardium (p=0.002). Moreover, in patients with viable myocardium, the greatest increase of ejection fraction occurred 1 month after surgery (9 ± 1%), whereas in those patients with negative DSE the ejection fraction increased more gradually (2±1% after 1 month, p=0.002 between groups for 1 month vs preoperative value), but still improved after 12 months follow-up (p<0.0001 in time for both groups). CONCLUSIONS: It appears that patients with LV dysfunction, but without viable myocardium, may also benefit from myocardial revascularisation. Functional recovery continuously occurs throughout the first year after surgical treatment.

Short QT interval is unreliable marker of anabolic androgenic steroid abuse in competitive athletes.

INTRODUCTION: Previous animal and human studies provided the evidence that testosterone may affect ventricular repolarization by shortening of the QT interval. Synthetic derivatives of testosterone, modified to enhance its anabolic properties, are occasionally abused by some competitive athletes. OBJECTIVE: We assessed whether the QT interval duration could discriminate androgenic anabolic steroids (AAS)-using strength athletes (SA) from drug-free endurance athletes (EA), by comparing 25 formulas for QT interval correction. METHODS: We recruited 22 elite male athletes involved in long-term strength or endurance training and 20 sedentary controls. All elite SA reported AAS abuse, whereas EA and controls were AAS-free. RESULTS: AAS-using SA had markedly shorter QT-interval than AAS-free EA (348 +/- 42.3 vs. 400 +/- 34.2 ms; p < 0.001). Also, drug-free EA had a significantly longer QT-interval than sedentary persons (400 +/- 34.2 vs. 358 +/- 18.9 ms; p < 0.01). In contrast, no significant difference in the QT-interval duration was observed between AAS users and control group (348 +/- 42.3 vs. 358 +/- 18.9 ms; p = 0.394). After the QT interval was adjusted for heart rate (HR) according to 25 different formulas, only the Ashman equation yielded considerable differences among the groups that were in line with those observed before correction. CONCLUSION: Inconsistent results obtained by different correction formulas along with inability to discriminate QT (QTc) interval duration between AAS-misusing athletes and control group do not support the use of QT (QTc) interval for anti-doping purposes.