Effect of cryoballoon and radiofrequency ablation for pulmonary vein isolation on left atrial function in patients with nonvalvular paroxysmal atrial fibrillation: A prospective randomized study (Cryo-LAEF study).

BACKGROUND: Isolation of the pulmonary veins (PVI) has become a mainstay in atrial fibrillation (AFib) therapy. Lesions in left atrial tissue lead to scar formation and this may affect left atrial function. METHODS: Patients with paroxysmal AFib were randomly assigned in a 1:2 allocation scheme to radiofrequency (RF) ablation or cryoballoon. Real-time three-dimensional echocardiography was performed (under sinus rhythm in all cases) before ablation and at 1 and 3 months to evaluate the left atrial functional indices. The primary outcome measure was change in left atrial ejection fraction (LAEF) at 1 month. RESULTS: 120 patients were randomized (80 to cryoballoon, 40 to RF). The absolute change in LAEF at 1 month was 4.0 (Q1-Q3, -0.1to 7.6)% in the cryoballoon group and -0.8 (Q1-Q3, -1.9 to 0.9)% in the RF group (P < 0.001 for the comparison between groups). At 3 months, the corresponding changes were 6.7 (Q1-Q3, 3.4-11.2)% and 0.7 (Q1-Q3, -0.7 to 3.5)%, respectively (P < 0.001). Overall, the rate of patients with lower LAEF at 3 months compared to baseline was 2.5% in the cryoballoon group and 32.5% in the RF group (P < 0.001). AFib recurrence rate at 6 months was higher in patients with decreased LAEF (odds ratio, 6.2; 95% confidence interval, 2.0-19.5; P = 0.002). CONCLUSION: The Cryo-LAEF study prospectively compared the effects of RF and cryoballoon ablation on left atrial function. Both at 1 and 3 months postablation, LAEF was either improved or stable in both ablation groups.

Severe mitral regurgitation coexisting with descending thoracic aorta aneurysm: staged approach using endovascular repair.

We describe the case of a 67-year-old man who was referred for the management of severe mitral valve regurgitation and coronary artery disease. Further workup revealed a descending thoracic aorta aneurysm. He underwent mitral valve replacement with coronary artery bypass surgery and, at a second stage, endovascular stent graft repair of the descending thoracic aorta aneurysm.

Diagnostic approach in symptomatic or asymptomatic aneurismal disease of the coronary arteries: a case report and five-year angiographic follow up.

Coronary artery aneurysms are rare anomalies that are usually incidental findings in coronary angiography. We present the case of a 64-year-old male patient with a recent episode of epigastric pain, nausea and vomiting, accompanied by electrocardiographic alterations and positive troponin I. As the symptoms persisted, the patient was referred for coronary angiography, during which a significant degree of aneurysmal dilatation was found in all three coronary vessels along their length. Oral administration of anticoagulants was decided upon. After five years of follow up, a new coronary angiogram was recorded, which showed no aggravation of the aneurysmal dilatations, while the patient was free of symptoms.

Estimation of atrial fibrillation recency of onset and safety of cardioversion using NTproBNP levels in patients with unknown time of onset.

OBJECTIVE: As shown previously in patients with new-onset atrial fibrillation (AF) without symptoms or signs of heart failure, N-terminal pro-brain natriuretic peptide (NTproBNP) increases rapidly, reaching a maximum within 24-36 h, and then decreases even if AF persists. A study was undertaken to use NTproBNP measurements in patients with AF of unknown time of onset to identify patients with presumed recent onset of the arrhythmia. DESIGN: Two-group open cross-sectional study. SETTING: Hospitalised patients in cardiology departments of four hospitals. PATIENTS: Patients presenting with AF of unknown onset and no signs or symptoms of heart failure were separated into two groups: group A with NTproBNP above the cut-off level and group B with a low NTproBNP level. INTERVENTIONS: No therapeutic intervention. All patients underwent transoesophageal echocardiography (TEE). MAIN OUTCOME MEASURES: Presence of left atrial thrombus on TEE. RESULTS: In group A (N=43) only two patients (4.7%) were found to have an atrial thrombus on TEE (negative predictive value of raised NTproBNP levels 95.3%) compared with 13 of 43 patients in group B (30.2%; p=0.002). Patients with a higher CHA(2)DS(2)VASc score (p=0.002) and a larger left atrium (p<0.001) were more likely to have an atrial thrombus. In the multivariate analysis, NTproBNP below the cut-off level was the most powerful predictor of the presence of thrombus (OR 25.0; p=0.016). CONCLUSION: The reported strong correlation between raised NTproBNP levels and the absence of atrial thrombi on TEE suggests that the short-term increase in NTproBNP levels after AF onset might be used to assess the age of the arrhythmia and thus the safety of cardioversion in patients with AF of unknown onset and no heart failure.

The impact of moderate aerobic physical training on left ventricular mass, exercise capacity and blood pressure response during treadmill testing in borderline and mildly hypertensive males.

INTRODUCTION: We sought to investigate the effect of moderate physical exercise on left ventricular mass, exercise tolerance and blood pressure response during treadmill testing, in middle-aged pre-hypertensive and mildly hypertensive men without any evidence of coronary heart disease. METHODS: Forty of 52 male borderline and mildly hypertensive subjects (mean age 53 ± 7 years old) with a normal treadmill exercise test and echocardiographic evaluation were randomly assigned to an exercise rehabilitation programme. Patients in the exercise group participated in an aerobic exercise program for 16 weeks, three times per week, at 60 to 80 percent of the maximum heart rate achieved during the preceding exercise test. RESULTS: At baseline no statistically significant differences between the two groups were observed in METS, in left ventricular mass index, or in blood pressure measurements at rest and during treadmill testing. Sixteen weeks later the exercise group showed higher values of METS compared to the control group (p<0.001), while changes in METS from baseline to 16 weeks' follow up differed significantly between the two groups (p<0.001 for group-time interaction). Additionally, 16 weeks after randomisation, systolic/diastolic blood pressure and heart rate were significantly lower in the exercise group compared to the control group at all stages of stress testing. Finally, the left ventricular mass index decreased significantly in the exercise group (118.80 ± 3.89 to 96.10 ± 8.95 kg/m) during the 16 weeks of intervention. CONCLUSION: This study revealed the beneficial effect of regular exercise training on left ventricular mass index, exercise capacity and systolic/diastolic blood pressure levels in borderline hypertensive patients.

Comparison of muscle functional electrical stimulation to conventional bicycle exercise on endothelium and functional status indices in patients with heart failure.

The aim of this prospective, open-label, cohort study was to compare the effect of muscle functional electrical stimulation (FES) on endothelial function to that of conventional bicycle training. Eligible patients were those with New York Heart Association class II or III heart failure symptoms and ejection fractions ≤ 0.35. Two physical conditioning programs were delivered: FES of the muscles of the lower limbs and bicycle training, each lasting for 6 weeks, with a 6-week washout period between them. Brachial artery flow-mediated dilation (FMD) and other parameters were assessed before and after FES and the bicycle training program. FES resulted in a significant improvement in FMD, which increased from 5.9 ± 0.5% to 7.7 ± 0.5% (95% confidence interval for the difference 1.5% to 2.3%, p < 0.001). Bicycle training also resulted in a substantial improvement of endothelial function. FMD increased from 6.2 ± 0.4% to 9.2 ± 0.4% (95% confidence interval for the difference 2.5% to 3.5%, p < 0.001). FES was associated with a 41% relative increase in FMD, compared to 57% with bicycle exercise (95% confidence interval for the difference between the relative changes 1.2% to 30.5%, p = 0.034). This resulted in attaining a significantly higher FMD value after bicycle training compared to FES (9.2 ± 0.4% vs 7.7 ± 0.5%, p < 0.001). In conclusion, the effect of muscle FES in patients with heart failure on endothelial function, although not equivalent to that of conventional exercise, is substantial. Muscle FES protocols may prove very useful in the treatment of patients with heart failure who cannot or will not adhere to conventional exercise programs.

Adverse bioeffects of ultrasound contrast agents used in echocardiography: true safety issue or "much ado about nothing"?

Ultrasound contrast agents, consisting of gas-filled microbubbles, have long been used to enhance ultrasonographic imaging of various organs and in several settings. In echocardiography, after their first use for Doppler signal enhancement, their applications have expanded and several studies, combining a range of stress modalities with myocardial contrast echocardiography have shown the clinical utility of these agents. In experimental isolated heart animal models, the interaction of ultrasound with echo-contrast microbubbles was shown to have significant biologic effects when the acoustic energy of the beam exceeded a threshold, leading them to rupture and causing cavitation phenomena; the observed consequences in the experimental setting included microvascular damage, transient decrease of contractile performance and increased lactate production. From the clinical point of view, the reporting of a number of serious adverse events - whose association with the echo-contrast agents was debated - has led to the addition of warning boxes in the prescribing documentation of these preparations. On the other hand, clinical studies including high numbers of patients have shown good safety and tolerance of contrast use during stress echocardiography, both for left ventricle opacification and myocardial perfusion imaging. The present review aims at presenting a balanced account of the existing data regarding the mechanisms and clinical implications of echo-contrast bioeffects, in order to make an informed assessment of their safety in clinical practice.

Effect of biventricular pacing on ventricular repolarization and functional indices in patients with heart failure: lack of association with arrhythmic events.

AIMS: We prospectively assessed the effects of biventricular (BiV) pacing on electrocardiographic (ECG) and vectorcardiographic (VCG) descriptors of ventricular depolarization and repolarization and their association with appropriate implantable cardioverter defibrillator (ICD) activation. METHODS AND RESULTS: We studied 70 consecutive heart failure (HF) (37 ischaemic) patients (64 males, age 66.3 years) with a history of syncope or sustained ventricular tachycardia (VT) who underwent implantation of a BiV-ICD. An invasive electrophysiological study (EPS) was performed before the implantation and 12-lead digital ECGs before and 30 days after implantation. Serial echocardiographic studies were performed. Follow-up duration was 1 year. Maximum (P < 0.001) and minimum (P = 0.004) QT intervals were significantly decreased, whereas QT dispersion was not altered (P = 0.086). QRS duration was shortened (P < 0.001), whereas QRS dispersion was significantly decreased (P = 0.034). Spatial T and QRS vector amplitudes decreased (P < 0.001, for both), whereas the spatial QRS-T angle was not affected (P = 0.671). Twenty-seven (38.6%) patients, experienced appropriate ICD therapies during follow-up. None of the ECG or VCG parameters (pre- or post-implant) were able to identify patients with appropriate ICD therapies during follow-up. Only the presence of a previous episode of sustained VT (spontaneous or inducible on EPS) was strongly associated with appropriate ICD therapies (multivariate P = 0.00 014; odds ratio 24.5). CONCLUSION: Improvement or no alteration of ECG and VCG descriptors of ventricular depolarization and repolarization was demonstrated after implantation of a BiV-ICD in HF patients. None of these parameters were associated with appropriate ICD therapies, whereas a previous episode of VT or induction of sustained VT on EPS predicted appropriate ICD treatments.

The role of sex and biochemical markers of inflammation in left ventricular remodelling, before and after surgery, in elderly patients with aortic valve stenosis.

INTRODUCTION: The aim of this study was to determine whether sex and biochemical markers of inflammation have a role in left ventricular (LV) remodelling after aortic valve replacement in elderly patients with aortic valve stenosis. METHODS: We studied 52 elderly patients with aortic valve stenosis (32 men, mean age 65 +/- 11 years and 20 women, mean age 68 +/- 9 years). Body surface area did not differ between men and women (1.81 +/- 0.15 versus 1.84 +/- 0.20, respectively). All patients underwent a complete echocardiographic examination for the determination of ejection fraction (EF), LV mass and mass index, peak and mean systolic pressure gradient, aortic valve area, early (E) and late (A) transmitral flow wave velocities and their ratio (E/A), tissue Doppler indexes of the mitral annulus (Sa, Ea, Aa), and the E/Ea ratio. In addition, levels of high sensitivity C-reactive protein (hsCRP), tumour necrosis factor-alpha (TNF-alpha) and monocyte chemoattractant protein-1 (MCP-1) were measured from venous blood samples taken before, and 10 days, 3 months and 6 months after aortic valve replacement. RESULTS: LV mass decreased from 297 +/- 99.7 g before aortic valve replacement to 210 +/- 67 g 3 months after surgery and to 210 +/- 74 g 6 months after surgery (p<0.001). LV EF did not change significantly (p=0.836). Peak and mean systolic pressure gradients decreased, whereas aortic valve area increased after valve replacement (p<0.001). These changes were similar in men and women. In women Sa was greater (p=0.017) and the E/Ea ratio lower (p=0.025) than in men. The long-term changes in peak and mean pressure gradients, aortic valve area and LV mass after aortic valve replacement were well correlated with the long-term changes in hsCRP, TNF-alpha and MCP-1 in both men and women. CONCLUSIONS: LV remodelling is similar in elderly men and women with aortic valve disease who have similar body surface area. Although inflammatory markers are not correlated with echocardiographic parameters before aortic valve replacement, a strong correlation exists after operation. This correlation is similar in men and women.

Atherosclerosis of the aorta in patients with acute thoracic aortic dissection.

BACKGROUND: The role of atherosclerosis in thoracic aortic dissection has not been established yet. Transesophageal echocardiography (TEE) is an imaging modality widely used in the diagnostic evaluation of thoracic aortic dissection, and it can detect aortic atherosclerotic plaques and assess their size and specific characteristics. METHODS AND RESULTS: One hundred consecutive patients with thoracic aortic dissection and adequate imaging of the thoracic aorta by TEE were studied. The type of dissection (proximal or distal) and the presence and the degree of aortic atherosclerosis were defined. Proximal aortic dissection (Stanford type A) was found in 64 patients. Patients with proximal dissection were younger than those with distal (type B; 58+/-13 vs 67+/-11 years, p<0.001). The prevalence of arterial hypertension was higher in patients with distal dissection compared with those with proximal. Aortic atherosclerosis was present in less patients with proximal than with distal dissection (67% vs 94%, p<0.002). Logistic regression analysis revealed that patients with severe atherosclerosis were 7.6-fold more probable to have type B than type A dissection (p<0.001). CONCLUSION: Aortic atherosclerosis is more associated with distal than with proximal aortic dissection.

Thoracic aorta atherosclerosis burden index predicts coronary artery disease in patients undergoing transesophageal echocardiography.

AIMS: The severity of thoracic aortic atherosclerosis (TAA) is associated with the extent of coronary artery disease (CAD). The aim of this study is to quantitative this relationship by developing a novel atherosclerotic index. METHODS AND RESULTS: Two hundred and forty six consecutive patients underwent transesophageal echocardiography (TEE) and coronary angiography. A grading system was used to define the extent of TAA for individual segment of the thoracic aorta. TAA burden index (TAABI) was defined as the sum of the grading for each segment. Of the derived values TAABI had the greatest specificity and sensitivity in predicting CAD. A TAABI of greater than 6 was associated with 16-fold increase in the probability of CAD with a specificity of 88% and a sensitivity of 81%. The positive predictive value was 77% and the negative predictive value 90%. CONCLUSION: A TAABI value of greater than 6 accurately predicts the presence of CAD. Patients with no or mild TAA are at low risk of having angiographically significant CAD.

Dobutamine stress echocardiography for the evaluation of cardiac reserve late after Fontan operation.

INTRODUCTION: This study aimed to assess the potential role and safety of dobutamine stress echocardiography (DSE) in the evaluation of cardiac reserve in asymptomatic patients several years after a Fontan operation. METHODS: We studied 10 asymptomatic patients, 28 +/- 5 years old, 14 +/- 6 years after their Fontan operation. All patients and 10 healthy, matched controls underwent two-dimensional and Doppler echocardiography at baseline and throughout dobutamine infusion (given in 3-minute increments of 5, 10, 20, 30, and 40 microg/kg/min). Multivariate analysis for repeated measurements was used to detect differences between patients and controls. RESULTS: There were no adverse events during dobutamine infusion. Heart rate increased appropriately in both patients and controls. Patients reached peak stroke volume at infusion rates of 20 microg/kg/min, whereas controls peaked at 10 microg/kg/min. Mean stroke volume, cardiac output and cardiac index were significantly different between the two groups only up to infusion rates of 10 microg/kg/min. The velocity time integral of the left ventricular outflow tract flow was significantly lower in patients than controls throughout the study. CONCLUSION: DSE is a safe method of stress testing for the assessment of adult Fontan patients and provides insights into the pathophysiology of their cardiac performance. Cardiac reserve in these patients is impaired compared to healthy controls.

The diagnostic value of adenosine stress-contrast echocardiography for diagnosis of coronary artery disease in hypertensive patients: comparison to Tl-201 single-photon emission computed tomography.

BACKGROUND: The use of the vasodilating agent adenosine as stressor in conjunction with myocardial contrast echocardiography has not been extensively evaluated in hypertensive patients. Our aim was to evaluate the diagnostic value of adenosine myocardial contrast echocardiography (MCE) in comparison to single-photon emission computed tomography (SPECT), with reference to angiographic findings, in a hypertensive population. METHODS: Fifty hypertensive subjects, treated with standard antihypertensive treatment, were submitted to adenosine stress MCE, adenosine SPECT, and coronary angiography within a 1-month period, without any intervening events. RESULTS: Sensitivity, specificity, and accuracy were 88%, 89%, 88% for MCE and 80%, 94%, 85% for SPECT, respectively (P = not significant). In the analysis by coronary territory, it appears that MCE and SPECT are both more accurate in detecting lesions of the anterior than of the posterior coronary system, as suggested by the good concordance to angiography results in the left anterior descending artery territory (k = 0.640 and 0.671, respectively). Agreement with angiographic findings was moderate for the right coronary artery (k = 0.561 and 0.539, respectively), whereas left circumflex artery lesions were more accurately detected by MCE than by SPECT (k = 0.533 and 0.400, respectively), that is, MCE appears to be superior in the left circumflex artery territory. CONCLUSIONS: In hypertensive patients, adenosine MCE has similar overall diagnostic accuracy with SPECT for assessment of coronary artery disease but is superior in the left circumflex artery territory.

Time course of C-reactive protein, tumour necrosis factor-alpha and monocyte chemoattractant protein-1 following the surgical treatment of patients with aortic valve stenosis.

INTRODUCTION: Patients with aortic valve stenosis show elevated levels of inflammatory markers in peripheral blood. The aim of this study was to investigate the time course of changes in these markers and to look for sex-related changes in their biological behaviour following aortic valve replacement. METHODS: We studied 52 patients (32 men, 20 women) who underwent aortic valve replacement and had no concomitant coronary artery disease. Men and women did not differ significantly with respect to age, body surface area, or body mass index. Levels of high sensitivity C-reactive protein (hsCRP), tumour necrosis factor-alpha (TNF-alpha) and monocyte chemoattractant protein-1 (MCP-1) were measured from venous blood samples taken before, and 10 days, 3 months and 6 months after aortic valve replacement. RESULTS: Baseline hsCRP levels were 5.34 +/- 5.71 mg/dl and 7.64 +/- 7.46 mg/dl for men and women, respectively. Levels increased significantly at 10 d (49.11 +/- 32.15 and 51.63 +/- 34.3 mg/dl, p < 0.001), then reduced at 3 m (5.85 +/- 5.04 and 8.49 +/- 7.69 mg/dl, p < 0.001) and 6 m (3.41 +/- 0.83 and 7.84 +/- 7.32 mg/dl, p < 0.001). Women had higher levels than men at 6 m (p = 0.027). Levels of TNF-alpha reduced progressively, from 212.4 +/- 119.5 and 255.7 +/- 171.3 pg/ml at baseline, to 121.6 +/- 47.7 and 150.0 +/- 33.5 pg/ml at 10 d, 134.7 +/- 25.3 and 138.6 +/- 30.9 at 3 m, and 48.7 +/- 8.8 and 44.9 +/- 10.5 pg/ml at 6 m (p < 0.001). MCP-1 levels also reduced progressively, from 157 +/- 64.8 and 145.6 +/- 13.4 pg/ml at baseline, to 128.6 +/- 18.8 and 122.7 +/- 10.3 pg/ml at 10 d, 49.0 +/- 12.4 and 56.6 +/- 11.5 pg/ml at 3 m, and 29.1 +/- 6.4 and 30.6 +/- 7.3 pg/ml at 6 m (p < 0.001). The time course of the changes in these indexes was identical for men and women, except that 6 m hsCRP levels were significantly higher in women. CONCLUSIONS: After aortic valve replacement, hsCRP levels show an early increase followed by a decrease, whereas both TNF-alpha and MCP-1 are reduced progressively. The time course curve is identical in men and women, except that hsCRP levels are higher in women than in men 6 months after aortic valve replacement.

Pre-ejection tissue-Doppler velocity changes during low dose dobutamine stress predict segmental myocardial viability.

INTRODUCTION: We tested the hypothesis that low dose dobutamine stress echocardiography (LDDSE) combined with tissue Doppler imaging (TDI) can be used for the quantitative assessment of the content of viable myocardium. METHODS: Forty-one patients with coronary artery disease and left ventricular dysfunction (ejection fraction < or =40%), already scheduled for revascularisation, underwent echocardiographic assessment of viability at rest and during low-dose dobutamine infusion (2.5 microg/kg/min up to 10 micro/kg/min) at two time points, 2 days before and 3 months after revascularisation. Pulsed-wave TDI was performed at rest and during LDDSE; ejection (Ej), pre-ejection (pre-Ej) and diastolic velocities (Ea, Aa) were recorded at rest and at 10 microg/kg/min dobutamine infusion. Recovery of regional function was defined as improvement of one or more grades 3 months post-revascularisation. RESULTS: A total of 112 vessels were revascularised. Out of 492 segments, 274 segments were characterised as viable and the remaining 218 as non-viable, according to postoperative functional myocardial recovery. Conventional qualitative LDDSE showed a sensitivity of 78% and specificity of 85% in predicting myocardial recovery. Ej, pre-Ej and Ea velocities increased significantly during LDDSE, while Aa velocity did not change significantly. Using ROC curves, the optimal cut-off value for viability assessment was an increase of 0.5 cm/s in Ej during LDDSE (80% sensitivity and 88% specificity, area under the curve 0.801), 0.6 cm/s in pre-Ej (91% sensitivity and 90% specificity, area under the curve 0.890), and 0.44 cm/s in Ea velocity (80% sensitivity and 81% specificity, area under the curve 0.780). CONCLUSIONS: Despite its technical limitations, the measurement of ejection and pre-ejection velocities during dobutamine stimulation appears to be an effective way of predicting myocardial segmental recovery following reperfusion.

Real-time three-dimensional dobutamine stress echocardiography for coronary artery disease diagnosis: validation with coronary angiography.

OBJECTIVE: To compare real-time three-dimensional echocardiography (RT3DE) with two-dimensional dobutamine stress echocardiography (2DE) for the detection of myocardial ischaemia, with angiographic validation of the results. METHODS: 56 patients (mean (SD) age 64.5 (6.2) years, 38 males), referred for coronary angiography, were examined by 2DE and RT3DE during the same dobutamine stress protocol. RESULTS: All 56 patients completed the stress protocol uneventfully. The mean (SD) acquisition time for the necessary views to evaluate all segments was 26.3 (2.5) s for RT3DE and 58.8 (3.7) s for 2DE (p<0.001). At peak stress, RT3DE had a higher wall-motion score index (1.25 (0.24) by 2DE, 1.30 (0.27) by RT3DE; p = 0.014). The regional wall-motion score for the four apical segments at peak stress was compared; it was 1.35 (0.55) by 2DE and 1.52 (0.69) by RT3DE (p = 0.003). The diagnostic parameters of 2DE versus RT3DE were: sensitivity 73% vs 78%, specificity 93% vs 89% and overall accuracy 86% vs 85%, respectively. In the left anterior descending artery territory, in particular, where RT3DE had higher regional wall-motion scores, it showed a tendency towards higher sensitivity (85% vs 78%), although this difference did not achieve statistical significance. CONCLUSION: RT3DE identifies wall-motion abnormalities more readily in the apical region than 2DE, which may explain the tendency towards higher sensitivity in the left anterior descending artery territory. RT3DE results were validated using angiography as reference and findings indicate diagnostic equivalence to 2DE, with the advantage of considerable shorter acquisition times.

Acute thoracic aortic thrombosis after intra-aortic balloon pumping.

We present two transesophageal echocardiographic images of a patient with acute myocardial infarction, demonstrating a large thrombus attached to the thoracic aortic wall, considered to be a complication of intra-aortic balloon pumping. The patient had received the device because of hemodynamic instability due to an infarct-related ventricular septal defect. Clinical manifestations which led to the diagnosis of thromboembolism were abdominal pain and deterioration of renal function, without signs of limb ischemia.

Changes in aortic root function after valve replacement in patients with aortic stenosis.

BACKGROUND: Aortic elastic properties are compromised in various states that induce functional and histological changes in the aortic wall. Aortic stenosis is frequent and often requires replacement of the stenotic valve. The purpose of this study was to examine the effect of aortic valve replacement on the aortic root function. METHODS: 31 patients, mean+/-SD age 67.2+/-9.1 years with severe aortic stenosis, who underwent aortic valve replacement with a bileaflet mechanical prosthesis, were studied. Aortic root function indices such as aortic cross-sectional compliance (CSC), aortic root distensibility (ARD), and aortic stiffness index (ASI) were calculated with the use of M-mode echocardiography in three sessions: one preoperatively (pre-op), one on day 7 postoperatively (early post-op), and one 6 months postoperatively (late post-op). RESULTS: Aortic root function deteriorated early post-op (p<0.001 for all) and returned towards pre-op levels late post-op (p=NS for all). CSC changed from 2.84+/-1.98 to 1.37+/-0.92, and 2.30+/-1.11 cm2/mmHg, ARD from 2.21+/-5.60 to 1.01+/-0.67, and 1.79+/-0.96 cm2/dyne, and ASI from 9.72+/-5.60 to 24.65+/-19.10, and 11.51+/-7.85, respectively. Correlations were found between early changes in some aortic root indices and the degree of aortic stenosis, denoting that aortic function deteriorated less in more severe cases of aortic stenosis. None of the late changes were related to aortic valve or left ventricular indices. CONCLUSIONS: Aortic valve replacement with a mechanical valve results in a significant but transient impairment of aortic distensibility.