Influence of myocardial viability on responsiveness to cardiac resynchronization in ischemic dilated cardiomyopathy: a prospective observational cohort study.

OBJECTIVE: To understand whether patients with post-ischemic dilated cardiomyopathy and myocardial viability (MV) could benefit from cardiac resynchronization therapy (CRT) in terms of clinical, echocardiographic and neuro- hormonal parameters compared to patients without MV. METHODS: One hundred and four consecutive patients were enrolled in a prospective observational cohort study. Using dobutamine stress echocardiography, 2 groups were identified: group A of 51 patients with MV and group B of 53 patients without MV. All patients were implanted with biventricular pacing devices combined with an internal cardioverter-defibrillator. Clinical, echocardiographic and neuro-hormonal parameters were evaluated at baseline and at six month follow-up. Analysis of variance for repeated measures on each variable suggestive of remodeling was performed. We considered responder every patient with: decrease of > 15% in left ventricular volumes and/or improvement in left ventricular ejection fraction of > 5% in addition to NYHA class improvement. RESULTS: All the variables improved in both groups (time effect). Comparing the two groups (group effect), the following variables were significantly better in group A: N-terminal pro-B-type natriuretic peptide (p=0.02), NYHA class (p=0.003), reverse remodeling (RR) (p=0.007), dP/dt (p=0.005), left ventricular ejection fraction (p=0.009), 3rd sound (p=0.01), and left ventricular end-systolic volume after the first week (p=0.035). RR occurred at the first week after CRT only in Group A and was maintained for all the time of this study. The maximum difference of the decrease of left ventricular volumes between the two groups occurred after the first week (p<0.001). CONCLUSION: Patients with MV responded better than patients without MV with a significant improvement after the first week from CRT.

Systo-diastolic ventricular function in patients with hypertension: an echocardiographic tissue doppler imaging evaluation study.

BACKGROUND: Tissue Doppler imaging (TDI) has evolved to become a useful non invasive method that can complement other echocardiographic techniques in the assessment of left ventricular function in different clinical conditions. Spectral pulsed TDI can provide measurements of regional systolic and diastolic myocardial velocities and is particularly useful in detecting abnormalities of left ventricular systolic and diastolic function. We investigated the presence of systo-diastolic dysfunction in patients (pts) with hypertension compared with pts affected by hypertensive cardiomyopathy and normal control subjects. METHODS: We evaluated 214 pts with traditional echocardiography and TDI: 69 normal control subjects (Group A); 145 pts with hypertension, divided according to base echocardiographic evaluation in 74 with no evidence of hypertensive cardiomyopathy (diastolic dysfunction and ventricular hypertrophy, Group B), and 71 with evidence of hypertensive cardiomyopathy (Group C). Pts groups were matched for age, sex, heart rate, smoking status and body surface area. RESULTS: There were no significant differences in ventricular diameters, volumes, shortening and ejection fraction values; TDI showed a progressive systolic wave peak reduction from Group A to B and from Group B to C. Routinely Doppler diastolic function did not show any significant difference between Group A and B; TDI showed progressive E wave peak velocity decrease and A wave peak velocity increase from Group A to B and C and from Group B to C. CONCLUSIONS: TDI evaluation showed a ventricular systolic dysfunction in pts with hypertensive cardiomyopathy; in addition, an early mild systo-diastolic dysfunction was detected in subjects with hypertension but no evidence of hypertensive cardiomyopathy.

Biphasic transoesophageal vs. transthoracic electrical cardioversion of persistent atrial fibrillation.

OBJECTIVE: To compare the efficacy and safety of transoesophageal (TOC) vs. transthoracic (TTC) electrical cardioversion, both with biphasic shocks, for sinus rhythm (SR) restoration in patients with persistent atrial fibrillation (AF). METHODS: We randomised 210 patients (151 male, 59 female, mean age 66 +/- 9 years) with persistent AF into two groups: group 1 (n = 104) undergoing TOC with a step-up protocol of 30, 50, 70 and 100 J, and group 2 (n = 106) undergoing TTC with a step-up protocol of 70, 100, 120 and 150 J. RESULTS: The two groups were homogeneous as for clinical and instrumental characteristics, except for left ventricular ejection fraction (50.5 +/- 10% in group 1 vs. 53 +/- 8% in group 2, P < 0.05) and thoracic impedance (63 +/- 8 Omega in group 1 vs. 66 +/- 6 Omega in group 2, P < 0.005). SR was restored in 98 (94%) group 1 patients vs. 99 (93%) group 2 patients (P = NS). First shock was effective in 48 (46%) group 1 patients vs. 54 (51%) group 2 patients (P = NS). Mean delivered energy was 50.4 +/- 23.6 and 95.1 +/- 29.6 J; mean effective energy was 47.3 +/- 20.7 and 91.2 +/- 26.6 J in group 1 and group 2, respectively. Cross-over to the highest energy level was never effective. TOC tolerability was optimal (mean discomfort score 1.2 on a 1-4 grading scale). Markers of myocardial necrosis did not increase and no procedure-related complications occurred. On logistic regression analysis, the most predictive variables of unsuccessful cardioversion were AF duration (P = 0.0001) and low left atrial appendage emptying velocity (P = 0.02). CONCLUSIONS: Both TOC and TTC with biphasic shocks are effective and safe for SR restoration in patients with persistent AF; however, the considerably lower levels of delivered and effective energies for SR restoration allow TOC to be performed during mild sedation with optimal tolerability, thus avoiding general anaesthesia.

Efficacy and safety of ibutilide vs. transoesophageal atrial pacing for the termination of type I atrial flutter.

AIMS: Comparing efficacy and safety of ibutilide vs. transoesophageal atrial pacing (ATP) for the termination of type I atrial flutter (AFL). METHODS AND RESULTS: Eighty-seven patients affected by AFL lasting between 2 h and 30 days were randomized in two groups: Group 1-i.v. ibutilide treatment, up to 2 mg, and Group 2-ATP, with "burst" and "ramp" pacing protocols. Sinus rhythm was restored in 36/45 (80%) patients in Group 1 vs. 18/42 (43%) in Group 2 (P<0.0005). In Group 1, mean AFL duration was 11.4 +/- 7.7 days in responders vs. 12.1 +/- 7.6 in non-responders (P=ns), while in Group 2 it was 2.7 +/- 1.4 vs. 14.2 +/- 5.4 days (responders vs. non-responders, respectively, P<0.0001); 30/36 (83%) responders in Group 1 had AFL >48 h vs. 10/18 (56%) responders in Group 2 (P<0.05). Non-sustained polymorphic ventricular tachycardia occurred in 2 patients in Group 1 vs. none in Group 2 (P=ns). It did not require any specific treatment except the interruption of ibutilide infusion. CONCLUSION: Both ibutilide and ATP proved to be safe and effective for recent onset type I AFL termination, but ibutilide was more effective when the arrhythmia had lasted longer than 48 h.

Comparative effects of irbesartan versus amlodipine on left ventricular mass index in hypertensive patients with left ventricular hypertrophy.

The aim of this study was to comparatively assess the effects of irbesartan and amlodipine monotherapies on left ventricular mass index (LVMI) in patients with mild to moderate untreated hypertension and echocardiographically determined left ventricular hypertrophy (LVH). Sixty hypertensive patients (35 men, 25 women; mean age, 52.8 years +/- 12.6) with diastolic blood pressure (BP) > or = 100 mm Hg were randomized to irbesartan 150 mg once daily or amlodipine 5 mg once daily for a 4-week titration period. Dosage of both drugs was increased to irbesartan 300 mg once daily or amlodipine 10 mg once daily in case of sitting diastolic BP still >90 mm Hg after the first 2 weeks of treatment. Dosage doubling was necessary in more than 50% of patients in both treatment groups. After the titration period, only the responders (sitting diastolic BP < or = 90 mm Hg) entered a 5-month maintenance period. After 3 months, echocardiographically estimated LVMI decreased by 23.2% in the irbesartan-treated patients and 11.4% in the amlodipine-treated patients, with an adjusted mean difference of 11.8% in favor of irbesartan (P < 0.0001). After 6 months, it decreased by 24.7% in the irbesartan-treated patients and 13.0% in the amlodipine-treated patients, with an adjusted mean difference of 11.6% in favor of irbesartan (P < 0.0001).