Biagio Liccardo

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.

Association between left atrial myocardial function and exercise capacity in patients with either idiopathic or ischemic dilated cardiomyopathy: A two-dimensional speckle strain study

BACKGROUND In patients with idiopathic dilated cardiomyopathy (DCM) a more depressed left atrial (LA) booster pump function has been observed compared to ischemic patients although under similar loading conditions, and attributed both to altered LA overload and to LA larger involvement in the myopathic process. AIM OF THE STUDY To detect by speckle-tracking two-dimensional strain (2DSE) LA systolic dysfunction in patients with either idiopathic or ischemic DCM, and to assess in these patients possible correlation between LA myocardial function and exercise capacity during cardiopulmonary test. METHODS Three-hundred-fourteen patients (52.4+/-11.2 years) with either idiopathic (160 patients) or ischemic (154 patients) DCM underwent cardiopulmonary stress test, standard Doppler echo and 2DSE analysis of atrial longitudinal strain in the basal segments of LA septum and LA lateral wall, and in LA roof. RESULTS The two groups were comparable for most of clinical variables. LV volumes, ejection fraction, stroke volume, and mitral valve effective regurgitant orifice were similar between the two groups. No significant differences were evidenced in Doppler transmitral inflow measurements. Also LA diameter and maximal volume were similar between the two groups. Conversely, LA active empting volume and fraction were both lower in patients with idiopathic DCM (<0.001). Peak systolic myocardial atrial strain was significantly reduced in patients with idiopathic DCM compared with ischemic DCM at the level of all the analyzed atrial segments (p<0.0001). By multivariable analysis, in the overall population, ischemic aetiology of DCM (p<0.0001) and LA volume (p<0.001) were the only independent determinants of LA lateral wall systolic strain. On the other hand, LA lateral wall systolic strain (p<0.0001) and LA volume (p<0.001) were powerful independent predictors of peak oxygen consumption during cardiopulmonary exercise testing. CONCLUSIONS Two-dimensional strain represents a promising non-invasive technique to assess LA atrial myocardial function in patients with DCM. LA systolic deformation is more depressed in idiopathic compared with ischemic DCM, and is closely associated with functional capacity during effort. Future longitudinal studies are warranted to further our understanding of the natural history of LA myocardial function, the extent of reversibility of LA dysfunction with therapy, and the possible prognostic impact of such indexes in patients with congestive heart failure.

Right ventricular myocardial adaptation to different training protocols in top-level athletes.

Objective: The aim of this study was to analyze right ventricular (RV) myocardial function in competitive athletes with left ventricular (LV) hypertrophy induced by either endurance or strength training. Methods: Standard Doppler echo, maximal electrocardiogram (ECG) ergometric test, and pulsed tissue Doppler (TD) of LV mitral annulus and of RV tricuspid annulus were performed in 32 competitive endurance athletes (long‐distance swimmers; ATE) and in 26 strength‐trained athletes (short‐distance swimmers; ATS), all males. By use of TD, the following parameters of myocardial function were assessed: systolic peak velocities (Sm), precontraction time, contraction time, early (Em) and late (Am) diastolic velocities, Em/Am ratio, and relaxation time. Results: The two groups were comparable for age, but ATS at rest exhibited higher heart rate, systolic blood pressure, and body surface area. LV mass index did not significantly differ between the two groups. However, ATS characterized increased wall thickness and relative wall thickness, whereas LV stroke volume and both LV and RV end‐diastolic diameters were greater in ATE. All transmitral and transtricuspid Doppler indexes were higher in ATE, with increased E/A ratios. TD analysis demonstrated in ATE higher Em and Em/Am ratio as well as longer relaxation time both at mitral and at tricuspid annulus level. In the overall population, distinct multiple linear regression models evidenced independent positive association between RV peak Em velocity and LV end‐diastolic diameter (P < 0.001) as well as independent direct correlation of the same RV peak Em velocity with both LV stroke volume and maximal workload achieved by bicycle ergometer (both P < 0.001). Conclusions: Right ventricular early diastolic myocardial function is positively influenced by preload increase in athletes, and represents an independent determinant of cardiac performance during physical effort. Therefore, pulsed TD may be taken into account to distinguish different cardiac adaptation to either endurance or strength sport activities, and eventually to quantify RV adaptation degree to long‐term training. (ECHOCARDIOGRAPHY, Volume 20, May 2003)

Perioperative clinical predictors of atrial fibrillation occurrence following coronary artery surgery

OBJECTIVE Atrial fibrillation (AF) is the most frequently encountered arrhythmic complication associated with coronary surgery. The aim of this paper was then to identify the clinical predictors of post-CABG AF occurrence. METHODS 150 consecutive patients were included in this study and divided into two groups according to the absence (SR group, 104 male and 22 female, age 58.4+/-8.8 years) or presence (AF group, 23 male and 1 female, age 65.4+/-6.3 years) of post-CABG AF. Forty-seven perioperative variables were considered. RESULTS After univariate analysis, advanced age (SR vs. AF: 58.4+/-8.8 vs. 65.4+/-6.3, P < 0.001), an increased BMI (SR vs. AF: 26.1+/-2.7 vs. 27.4+/-2.5, P = 0.026), a prior history of paroxysmal AF (SR vs. AF: 3.2% vs. 16.7%, P = 0.028), left atrial enlargement (SR vs. AF: 21.1% vs. 70.8%, P < 0.001) and a more severe coronary artery disease (CAD) (SR vs. AF: no. of diseased vessels: 2.42+/-0.7 vs. 2.91+/-0.3, P = 0.001; three-vessel CAD (54.1% vs. 91.3%, P = 0.002) were the only factors that statistically differed between the groups. Multivariate logistic regression analysis identified left atrial enlargement (P < 0.0001), a prior history of paroxysmal AF (P = 0.007) and a more severe CAD (P = 0.0047) to be independent correlates for AF. CONCLUSIONS Post-CABG AF seems to require a well definite anatomical and electrical substrate that is generated by increased left atrial dimensions, a greater extension of coronary lesions and a possible electrical remodeling consequent to prior repetitive episodes of paroxysmal AF.

Global longitudinal speckle-tracking strain is predictive of left ventricular remodeling after coronary angioplasty in patients with recent non-st elevation myocardial infarction

AIMS To test whether two-dimensional longitudinal strain (2DSE) performed after revascularization by percutaneous coronary intervention (PCI) could predict left ventricular (LV) remodeling in patients with recent non-ST elevation myocardial infarction (NSTEMI). METHODS In 70 patients (62.7 ± 8.7 years) with recent NSTEMI (between 72 hours and 14 days), undergoing coronary angiography for recurrent angina, myocardial deformation parameters were measured by 2DSE before and 24 hours after reperfusion therapy. Strain in all LV segments was averaged to obtain a global value (Global longitudinal Strain--GLS). Infarct size was estimated by clinical parameters and cardiac markers. After 6 months from intervention, LV negative remodeling was defined as lack of improvement of LV function, with increase in LV end-diastolic volume of greater than or equal than 15%. RESULTS At follow-up, patients were subdivided into remodeled (n=32) and non-remodeled (n = 38) groups. Patients with negative LV remodeling had significantly lower baseline LV ejection fraction (44.8±6.9 vs. 48.7 ± 5.5 %; p < 0.05), higher peak troponin I (p < 0.001) and reduced GLS (- 10.6±6.1 vs - 17.6 ± 6.7 % p < 0.001) than those without LV remodeling. GLS showed a close correlation with peak troponin I after PCI (r = 0.64, P < 0.0001) and LV WMSI (r = 0.42, p < 0.01). By multivariable analysis, diabetes mellitus (P < 0.005), peak of Troponin I after PCI (P < 0.0005), GLS at baseline (OR: 4.3; p < 0.0001), and lack of improvement of GLS soon after PCI (OR: 1.45, P < 0.01) were powerful independent predictors of negative LV remodelling at follow-up. In particular, a GLS ≤ 12 % showed a sensitivity and a specificity respectively of 84.8% and 87.8% to predict negative LV remodelling at follow-up. CONCLUSIONS in patients with recent NSTEMI, longitudinal LV global and regional speckle-tracking strain measurements are powerful independent predictors of LV remodeling after reperfusion therapy.

Prognostic value of pharmacological stress echocardiography in diabetic patients.

Our study was undertaken to assess the prognostic significance of pharmacological stress echocardiography in 325 diabetic patients. Pharmacological stress echocardiography was performed for diagnosis of coronary artery disease in 128 patients, and for risk stratification in 197 patients. Follow-up was 34 months. Cardiac-related death and non-fatal myocardial infarction were considered hard events. During the follow-up period, there were 38 deaths and 23 acute non-fatal myocardial infarctions. By univariate analysis, a pharmacological stress echocardiography positive response for ischaemia indicated an increased risk of cardiovascular death. However, by multivariate analysis, advanced age and peak ejection fraction <40% were the only independent predictors of cardiac death. The same peak ejection fraction (EF) <40%, rest wall motion score index and previous myocardial infarction were independent predictors of hard events. After dividing the population into two subgroups on the basis of EF at rest, only a peak EF <40% and a pharmacological stress echocardiography positive test were powerful independent predictors of cardiovascular mortality.

Usefulness of Doppler tissue imaging for the assessment of right and left ventricular myocardial function in patients with dual-chamber pacing

The aim of the study was to evaluate by Doppler tissue imaging (DTI) the combined effects of atrio-ventricular (AV) delay and heart rate (HR) changes on global and segmental right (RV) and left (LV) ventricular diastolic function in 15 patients with dual-chamber pacemakers paced in the DDD mode. RV and LV inflow velocities and regional systolic and diastolic pulsed-wave (PW) DTI parameters were analyzed at four different pacing modes: (1) HR 70 beats/min, AV delay 125 ms; (2) HR 70 beats/min, AV delay 188 ms; (3) HR 89 beats/min, AV delay 125 ms; (4) HR 89 beats/min, AV delay 188 ms. For each pacing mode selected, RV diastolic filling velocities always prevailed over LV ones. As for RV and LV adaptation to the four different stimulation protocols, a higher paced rate and a prolonged AV delay caused across both the AV valves a decrease of E wave and of E/A ratios. The intersegmental comparison of PW-DTI parameters outlined that RV free wall exhibited significantly higher peak systolic (Sm) and early-diastolic (Em) wall velocities, and longer systolic ejection time. Considering separately RV and LV segmental physiology at the four programmed pacing modes, an increase in HR determined a progressive shortening of systolic ejection times in all the segments analyzed. Moreover, in each region the Em/Am ratio decreased with higher HR and longer AV delay. Conversely, Em encountered a progressive reduction in RV free wall, while remaining quite unchanged in all the LV regions. Both ventricles shared a similar pattern of global and regional adaptation to programmed HR and AV delay modifications, consisting in a progressive greater contribution of late diastole to ventricular filling at higher HR and more prolonged AV delay. However, at a regional level the right ventricle exhibited higher systolic and diastolic wall velocities than all left ventricular regions.

Ventricular tachyarrhythmias following coronary surgery : predisposing factors

The perioperative factors potentially associated with post-coronary artery bypass grafting (CABG) ventricular tachyarrhythmias (VT) onset have not been deeply investigated. Monomorphic or polymorphic ventricular tachycardia and ventricular fibrillation represent the most dreadful arrhythmic events that can complicate the postoperative course of CABG. As a consequence, the aim of our paper was to identify which perioperative variables might predict post-CABG VT occurrence. One hundred and fifty-two consecutive patients who underwent CABG surgery at our Institution were included in the study. Post-CABG VT occurred in 13 out of 152 patients (8.5%, six cases of monomorphic ventricular tachycardia and seven cases of ventricular fibrillation). At univariate analysis, VT patients were significantly younger (54.8+/-6.6 vs. 60.1+/-8.8, P=0.038), exhibited a more severe coronary artery disease (CAD) (number of diseased vessels 2.92+/-0.3 vs. 2.45+/-0.7, P=0.023, and percentage of patients with three-vessel CAD 91.7% vs. 57.3%, P=0.043) and received a greater number of CABGs than those remaining in sinus rhythm (SR) (percentage of patients receiving three or more CABGs 76. 9% vs. 38.8%, P1000 76.9% vs. 38%, Pnormal range 72.7% vs. 30.7%, P=0.014), electrolyte derangement (84.6% vs. 45.6%, P=0.017) and a severe haemodynamic impairment (need for IABP 23% vs. 2.9%, P1000, postoperative electrolyte imbalance, the need for three or more CABGs and of IABP all were independent correlates for VT. In conclusion, post-CABG VT seem to be related to the preexistence of a severe underlying coronary artery disease along with perioperative triggering factors such as acute ischemia, electrolytic disorders and a sudden haemodynamic impairment.

Acute and Chronic Effects of Noninvasive Ventilation on Left and Right Myocardial Function in Patients with Obstructive Sleep Apnea Syndrome: A Speckle Tracking Echocardiographic Study

In patients with obstructive sleep apnea syndrome (OSAS), repetitive hypoxia due to sleep‐induced apnea adversely affects the interaction between myocardial oxygen demand and supply, resulting in the development of subclinical cardiac dysfunction. The purpose of the study was to analyze the different involvement of left and right heart myocardial function in patients with OSAS treated with noninvasive ventilation (NIV).

Perioperative correlates of malignant ventricular tachyarrhythmias complicating coronary surgery.

SummarySustained ventricular tachyarrhythmias (VT), such as monomorphic or polymorphic ventricular tachycardia, and ventricular fibrillation, represent the most serious arrhythmic events that can complicate the postoperative course of coronary artery bypass grafting (CABG). The perioperative factors potentially associated with post-CABG sustained VT onset have not been thoroughly investigated. As a consequence, the aim of our study was to identify which perioperative variables might predict post-CABG VT occurrence.One hundred and fifty-two consecutive patients who underwent CABG surgery at our Institute were included in the study. Post-CABG VT occurred in 13 out of 152 patients (8.5%, six cases of monomorphic ventricular tachycardia and seven cases of ventricular fibrillation). Univariate analysis revealed that VT patients were significantly younger (54.8 ± 6.6 vs 60.1 ± 8.8,P = 0.038), exhibited more severe coronary artery disease (CAD) (no. of diseased vessels, 2.92 ± 0.3 vs 2.45 ± 0.7,P = 0.023; and percentage of patients with three-vessel CAD, 91.7 vs 57.3%,P = 0.043), and received a greater number of CABGs than those remaining in sinus rhythm (SR) (percentage of patients receiving three or more CABGs, 76.9 vs 38.8%,P = 0.018) Moreover, VT patients more frequently developed intra- or postoperative myocardial infarction (total CK > 1000, 76.9 vs 38%,P = 0.016; and MB-CK > normal range, 72.7 vs 30.7%,P = 0.014), electrolyte derangement (84.6 vs 45.6%,P = 0.017), and a severe hemodynamic impairment (need for intra-aortic balloon pump (IABP), 23 vs 2.9%,P = 0.009). On multivariate analysis, total CK > 1000, postoperative electrolyte imbalance, the need for three or more CABGs, and for IABP all were independent correlates for VT.In conclusion, post-CABG VT seem to be related to the preexistence of a severe underlying coronary artery disease along with perioperative triggering factors, such as acute ischemia, electrolytic disorders, and sudden hemodynamic impairment.