Early textural and functional alterations of left ventricular myocardium in mild hypothyroidism.

The aim of the present study was to evaluate cardiac function and texture in patients with subclinical hypothyroidism (sHT) both by conventional and new ultrasonic intramyocardial tissue techniques. sHT was characterized by normal serum free tetraiodotironine and free triiodotironine levels and slightly increased serum TSH level. Twenty-four patients affected by sHT and 24 sex- and age-matched healthy volunteers were studied. All subjects were submitted to conventional two-dimensional (2D)-color Doppler echocardiography, pulsed wave tissue Doppler imaging (PWTDI) for the analysis of the diastolic function, color Doppler myocardial imaging (CDMI) for the analysis of regional strain and strain-rate and integrated backscatter (IBS) for the evaluation of intrinsic contractility and tissue characterization. The results of the present study were: (a) the detection in sHT subjects of a lower cyclic variation index (CVI) indicating an altered myocardial intrinsic contractility; (b) a higher ultrasonic myocardial reflectivity indicating an altered myocardial texture; (c) the detection of lower systolic strain and strain-rate indicating an alteration of myocardial regional deformability; (d) an initial impairment of left ventricular diastolic function indicated by a decrease of peak E mitral flow velocity and an increase of peak A mitral flow velocity. All parameters studied with conventional 2D-echo in sHT patients were comparable with controls, except for a mild alteration in diastolic function. A significant correlation among systo-diastolic modifications detected by CDMI and IBS and serum TSH levels were found. The CVI at septum, the PWDTI S-peak wave and the systolic strain at septum were inversely related to the serum TSH levels. In conclusion, the new intramyocardial ultrasonic techniques confirm and extend the previous knowledge on the effect of the sHT on the heart, allowing the detection of early ultrastructural and regional functional systolic and diastolic abnormalities.

Severe aortic stenosis and myocardial function: diagnostic and prognostic usefulness of ultrasonic integrated backscatter analysis.

BACKGROUND: The aim of this study was to assess the myocardial reflectivity pattern in severe aortic valve stenosis through the use of integrated backscatter (IBS) analysis. Patients with aortic stenosis (AS) were carefully selected in the Department of Cardiology. METHODS AND RESULTS: Thirty-five subjects (AS: valve orifice < or =1 cm2; 12 female; mean age, 71.8+/-6.2 years) and 25 healthy subjects were studied. All subjects of the study had conventional 2D-Doppler echocardiography and IBS. Backscatter signal was sampled at the septum and posterior wall levels. Patients with AS were divided into 2 groups: 16 patients with initial signs of congestive heart failure and a depressed left ventricular systolic function (DSF) (ejection fraction [EF] range, 35% to 50%) and 19 asymptomatic patients with normal left ventricular systolic function (NSF) (EF >50%). Myocardial echo intensity (pericardium related) was significantly higher at the septum and posterior wall levels in DSF than in NSF and in control subjects. IBS variation, as an expression of variation of the signal, appeared to be significantly lower in AS with DSF than in NSF and in control subjects, at both the septum and posterior wall levels. Patients with DSF underwent aortic valve replacement, and, during surgical intervention, a septal myocardial biopsy was made for evaluation of myocardium/fibrosis ratio. Abnormally increased echo intensity was detected in left ventricular pressure overload by severe aortic stenosis and correlated with increase of myocardial collagen content (operating biopsy). CONCLUSIONS: One year after aortic valve replacement, we observed a significant reduction of left ventricular mass, and, only if pericardial indexed IBS value (reduction of interstitial fibrosis) decreased, it was possible to observe an improvement of EF and of IBS variation.

Abciximab improves 6-month clinical outcome after rescue coronary angioplasty.

BACKGROUND: Few data are available concerning the effects on clinical outcome and left ventricular function of abciximab administration in patients undergoing rescue percutaneous transluminal coronary angioplasty (PTCA) after failed thrombolysis for acute myocardial infarction. The aim of the study was to investigate such effects. METHODS: Eighty-nine consecutive patients referred to our laboratory from other hospitals for rescue PTCA within 24 hours from the onset of chest pain were prospectively randomized before the procedure to abciximab treatment (44 patients) or placebo (45 patients). No significant differences in baseline characteristics were observed between the 2 groups. Study end points were the occurrence of major adverse cardiac events (MACE) such as death, reinfarction, congestive heart failure, target lesion revascularization, or recurrent ischemia at 30-day and 6-month follow-up and the occurrence of periprocedural bleeding. RESULTS: Mean time from symptom onset to reperfusion was 8.5 +/-5.4 hours; rescue PTCA was successful in 96% of patients. The incidence of major, moderate, and minor bleeding was similar in the 2 groups. At 30-day follow-up, the echocardiographic left ventricular wall motion score index showed a significantly higher improvement in the abciximab group versus the placebo group (P <.001). At 6-month follow-up, the incidence of MACE was 11% in the abciximab group versus 38% in the placebo group (P =.004). Abciximab administration (P =.003) and cardiogenic shock (P =.005) were the only independent predictors of the occurrence of MACE at multivariable analysis. CONCLUSION: Treatment with abciximab during rescue PTCA positively affects clinical outcome at 6-month follow-up without increasing periprocedural bleeding.