Luigi De Simone

Pulsed Doppler tissue imaging in endurance athletes: relation between left ventricular preload and myocardial regional diastolic function.

The aim of this study was to assess the effects of endurance training on myocardial regional systolic and diastolic function by pulsed Doppler tissue imaging (DTI). Twenty male water polo players and 20 male control subjects underwent standard Doppler echocardiography and pulsed DTI, performed in apical views by placing a sample volume on left ventricular (LV) basal septal and inferior walls. Age, body surface area, and blood pressure were comparable between the 2 groups, with lower heart rate in athletes (p <0.001). They had significantly increased LV mass index (due to both higher wall thickness and end-diastolic diameter), greater endocardial fractional shortening, higher transmitral early/atrial (E/A) peak velocities ratio. In athletes, DTI analysis showed significantly prolonged myocardial deceleration time and greater myocardial E/A peak velocity ratio of septal and inferior walls, whereas myocardial early peak velocity was increased (p <0.01) only at the inferior wall. In the overall group, we found univariate relations of septal and inferior E/A peak velocity ratio and myocardial deceleration time with LV mass levels, and, in particular, with the sum of wall thickness. By separate multivariate analyses, however, these relations disappeared, being dependent on heart rate degree. Another association found between LV end-diastolic diameter and myocardial early diastolic wave peak velocity of the inferior wall (r = 0.68, p <0.0001) remained significant (standardized beta coefficient 0.60, p <0.00001), even after adjusting for heart rate, body surface area, age, and stroke volume (R(2) = 0.71, p <0.00001). In conclusion, DTI is a useful tool for detecting regional changes in myocardial function induced by training, because athletes present with an improvement in diastolic passive properties of myocardium. The higher early diastolic velocity of the inferior wall and its relation to increased preload may represent an indicator of aerobic training, allowing quantification of the degree of LV adaptation to endurance exercise.

Use of pulsed Doppler tissue imaging to assess regional left ventricular diastolic dysfunction in hypertrophic cardiomyopathy

In this study, regional diastolic patterns and their relations with transmitral Doppler inflow were investigated in hypertrophic cardiomyopathy (HC) by pulsed Doppler tissue imaging (DTI). Doppler echocardiography and DTI of basal septum and lateral wall (apical 4-chamber view) were performed in 20 patients (15 men and 5 women) with HC and in 10 healthy subjects (7 men and 3 women). Diabetes, hypertension, coronary artery and valvular disease, mitral regurgitation, New York Heart Association functional classes III to IV, sinus tachycardia, atrial fibrillation, and inadequate echocardiograms were exclusion criteria. Peak velocity and time-velocity integral of early and late waves and their ratios, and deceleration and isovolumic relaxation times were determined by standard Doppler and by DTI at the septal and lateral wall levels. The 2 groups were comparable for age, heart rate, blood pressure, and ejection fraction. Transmitral peak velocity and time-velocity integral E/A ratios were reduced (both p <0.05) and deceleration and isovolumic relaxation times prolonged (both p <0.00001) in HC. Septal DTI showed lower peak velocity and time-velocity integral e/a ratios (p <0.00001 and p <0.001, respectively) and lengthened regional deceleration (p <0.01) and isovolumic (p <0.001) relaxation times. DTI of the lateral wall showed a prolongation of deceleration and isovolumic relaxation times (both p <0.01). By dividing HC according to transmitral E/A, 8 patients with E/A <1 had lower DTI septal e/a ratio (p <0.01) and prolonged septal deceleration and isovolumic relaxation times (both p <0.01) but no changes in DTI pattern of lateral wall than 12 patients with E/A > 1. In conclusion, DTI is useful and complementary to standard Doppler imaging to characterize diastolic properties in HC, reflecting a typical pattern of intramyocardial impaired relaxation at the level of hypertrophied septum and also providing information about the degree of this regional impairment. The lateral wall presents minor changes in diastolic times, which indicate how diastolic asynchrony is not confined to the hypertrophied segment in HC.

Positive association between circulating free insulin-like growth factor-1 levels and coronary flow reserve in arterial systemic hypertension.

BACKGROUND The reduction of coronary flow reserve (CFR) found in arterial hypertension may be due to changes in afterload, left ventricular (LV) structure, and metabolic factors. Also, insulin-like growth factor-1 (IGF-1) may be associated with the magnitude of CFR in relation to its modulating action on cardiac and endothelial function. METHODS A total of 44 newly diagnosed, untreated hypertensive patients, who were free of diabetes mellitus and coronary artery disease, underwent M-mode analysis, second-harmonic Doppler echocardiographic assessment of CFR (dipyridamole infusion 0.56 mg/kg intravenously in four patients), determination of circulating free IGF-1, and insulin resistance. Based on CFR levels, hypertensive subjects were divided into two groups: 18 with normal CFR (> or = 2) and 26 with impaired CFR (<2). RESULTS Patients with normal CFR had lower diastolic blood pressure, heart rate, and LV mass index but higher free circulating IGF-I than patients with reduced CFR (P < .001). Insulin resistance was not significantly different between the two groups. In a first multilinear regression analysis that included demographic and echocardiographic variables, insulin resistance was independently associated with CFR (standardized beta coefficient = -0.31, P < .05) in the overall population. However, in a subsequent model which included also IGF-1, the relationship between insulin resistance and CFR disappeared, whereas IGF-1 was the main independent determinant of CFR (beta = 0.51, P < .0002). CONCLUSIONS Free IGF-1 circulating levels are independently associated with CFR in hypertensive individuals free of overt coronary artery disease. A possible beneficial effect exerted by IGF-1 on coronary blood flow may be supposed in arterial hypertension.

Percutaneous mitral commissurotomy versus open mitral commissurotomy: a comparative study

OBJECTIVE Although many studies in medical literature are comparing percutaneous trans-septal mitral commissurotomy (PTMC) and open mitral commissurotomy (OMC), very few long-term comparative follow-ups are available. METHODS Between January 1991 and December 1997, 193 patients with isolated mitral stenosis were assigned either to PTMC (111 cases) or to OMC (82 cases). PTMC was performed in all cases with Inoue Ballon, OMC was performed with standard techniques. Categorical values were compared by chi square analysis, whereas continuous data were compared by Mann-Whitney test. Univariate survival and event free analysis (Kaplan-Meier+/-SE and log rank) were performed. Recurrent stenosis was classified any mitral valve area (MVA) less than 1.2 cm2 and whenever post-op. echo showed a loss more than 50% of the initial gain. Data were reported as mean+/-SD. Data concerning late echocardiographic assessment were studied with linear and logistic regression analysis. RESULTS The two groups were homogenous as far preoperative variables as sex, mean age, MVA, echo score and incidence of left atrial thrombosis were concerned. Mean NYHA was preoperatively higher in OMC (2.79+/-0.58) versus PTMC (2.42+/-0.5) (P = 0.001). There was no hospital mortality in both groups. Incidence of hospital complications was similar (4/ 111 after PTMC and 1/82 after OMC; P = 0.3). Seven year survival: 95.41+/-0.02 (PTMC) and 98.05+/-0.01 (OMC) (P = 0.3) and freedom from late complications did not show statistical differences: Embolism 98.78+/-0.01 in PTMC and 98.78+0.01 in OMC (P = 0.8); Recurrent stenosis 71.89+/-0.13 in PTMC versus 82.89+/-0.08 in OMC (P = 0.2); Reoperation 88.43+/-0.08 in PTMC versus 96.25+/-0.02 in OMC (P = 0.4). A larger MVA was found in patients undergone to OMC (2.05+/-0.35) versus PTMC (1.81+/-0.33) (P = 0.001). Furthermore mean NYHA was lower in OMC (1.14+/-0.3) versus PTMC (1.39+/-0.7) (P = 0.001). CONCLUSIONS Both techniques achieve with a low operative risk and low incidence of complications a good palliation of rheumatic mitral stenosis. Incidence of complications in the follow-up is similar. OMC allows a larger mitral valve area, a better functional recovery and a lower incidence of late mitral regurgitation.

Noninvasive Assessment of Left and Right Internal Mammary Artery Graft Patency with High-Frequency Transthoracic Echocardiography

OBJECTIVES The aim of this study was (1) to visualize internal mammary artery grafts (IMAG) on coronary artery by transthoracic echocardiography and (2) to assess the patency of the grafts. METHODS Twenty-three patients (21 men, 56 +/- 6 years) with previous coronary artery bypass grafting were studied at baseline and after they underwent low-dose dipyridamole infusion. The parameters obtained were systolic (SPV) and diastolic (DPV) peak velocities and their ratio (DPV/SPV); the dipyridamole infusion to baseline ratio of DPV was an index of IMAG blood flow reserve (FR). Two groups of patients were selected at baseline: group A, (n = 12) with a DPV/SPV >1, and group B (n = 11), with a DPV/SPV <1. RESULTS The IMAG was identified in all patients. Intraluminal flow signals obtained with pulsed wave Doppler showed a biphasic pattern (1 systolic and 1 diastolic wave). After dipyridamole infusion was administered, flow velocities increased in 11 of 12 patients in group A and in 5 of 11 patients in group B. In group A the DPV/SPV increased from 1.79 +/- 0.47 to 1.8 +/- 0.43 (P = not significant), and the FR was 1.8 +/- 0.4. In group B the DPV/SPV increased from 0. 46 +/- 0.05 to 0.5 +/- 0.09 (P = not significant), and the FR was 1. 3 +/- 0.41. Coronary angiography showed the graft patency in all patients in group A and in 5 patients in group B with increased flow velocity after dipyridamole infusion. In the identification of graft stenosis at baseline, DPV/SPV showed 100% sensibility and 58% specificity, and FR showed 92% sensibility and 84% specificity. CONCLUSION Doppler echocardiographic evaluation of the IMAG is a simple noninvasive method to assess the functional impairment of the vessel.