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Percutaneous aortic valve replacement is an emerging alternative for high surgical risk patients with native aortic valve stenosis. We describe for the first time a valve-in-valve procedure with a CoreValve prosthesis for the treatment of a severely stenotic degenerated aortic bioprosthesis.

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 ≤1 cm 2 ; 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.

Aim of the study was to assess the relative usefulness of transesophageal echocardiography (TEE) and X-ray computed tomography (CT) in the follow-up of patients who survived an aortic dissection.We evaluated 44 patients (age = 57 +/- 12 years) with treated aortic dissection: 14 had a De Bakey type I, 20 a type II and 1 patient a type III dissection treated surgically: 1 patient had a type I, 1 a type II and 7 a type III dissection treated medically. All entered an outpatient follow-up program with serial evaluations at 1, 6 and 12 months after initial diagnosis by dual noninvasive imaging protocol. A contrast-enhanced CT scan and a TEE with biplane probe were performed on the same day and in random order.A total of 252 evaluations with both CT and TEE were considered. A completely normal study was found in 45 TEE and 48 CT evaluations. The following abnormal findings could be documented by one or both techniques: thrombus in the false lumen (TEE: n = 48; CT: n = 45 evaluations); intimal flap (TEE and CT: n = 68); aortic dilatation (TEE and CT: n = 15); pericardial effusion (TEE and CT: n = 3); aortic pseudoaneurysm (TEE: n = 2; CT: n = 3); isthmic coarctation (TEE and CT: n = 1). Regarding the presence or absence of these abnormalities, which are within the diagnostic domain of both imaging techniques, the results were fully concordant in 245 studies, and discordant in 7, with an overall agreement of 97%. In addition, some abnormal findings could be detected by TEE only: aortic insufficiency (n = 36); intimal tear (n = 25); spontaneous echocontrast effect in the false lumen (n = 39 evaluations). Other abnormal findings could be detected by CT only: a pleural effusion in 4, a truncus anonymous dissection in 1, a pseudoaneurysm due to suture dehiscence of the distal anastomosis of the ascending aorta in 1 evaluation (which yielded ambiguous results by TEE, with turbulent flow departing from the graft).Both CT and TEE are atraumatic, safe and accurate techniques for serial follow-up imaging of patients treated for aortic dissection. Information provided by CT is largely redundant, rather than additive, to that provided by TEE. The latter should be probably preferred for shorter imaging time, accuracy and convenience, although CT might still play a role in selected cases of ambiguous TEE results.

It has been demonstrated that high dose (up to 0.84 mg/kg over 10 min) dipyridamole echocardiography stress testing is feasible even in the first few hours after coronary artery bypass graft surgery and can be used to assess the beneficial physiological effects of coronary revascularization as well as graft patency. The aim of this study was to assess the role of dipyridamole echocardiography testing performed shortly after myocardial revascularization in the stratification of prognosis during follow-up. We studied 49 consecutive patients (45 males and 4 females; mean age 56 ± 8 years) referred to our institute for elective myocardial revascularization. Six patients had single, 14 double, and 29 triple vessel disease. Forty-two left internal mammary artery grafts, 16 sequential venous grafts, and 45 single venous grafts were performed. All patients were submitted to dipyridamole echocardiography testing before (range 1–3 days) and shortly after (range 5–7 days) myocardial revascularization, always with the patients off antianginal medication. An arbitrary wall-motion score grading from 0 to 3 (normal, hypokinesia, akinesia, and dyskinesia) was applied to the seven regions into which the left ventricle was divided. Before surgery 48 patients showed wall-motion abnormalities during the test (47 patients also presented ECG changes). Angina occurred in 48 patients. One patient had ischemic ECG changes and angina. The mean wall-motion score was 3.11 per patient before and 6.5 per patient after the test (P < 0.001). During the test performed after myocardial revascularization, two patients showed wall-motion abnormalities, angina, and ECG ischemic changes; one patient showed wall-motion abnormalities and angina; two patients presented only ECG ischemic changes; one patient showed wall-motion abnormalities and angina; and two patients showed ischemic changes. The mean postsurgical wall-motion score was 2.5 per patient before and 2.8 per patient after the test (P = NS). Of the five patients with a positive test for echocardiographic and/or ECG criteria, five suffered events during a 1-year follow-up (two developed Q waves and resting wall-motion abnormalities; three had recurrence of angina); of the remaining 43 patients with a negative test for echocardiographic and ECG criteria, only two developed angina during follow-up. The incidence of postsurgical events was 100% in patients with a positive and 5% in patients with a negative dipyridamole echocardiography test early after myocardial revascularization (P < 0.001). In conclusion, our data demonstrate that dipyridamole echocardiography stress testing is a suitable method in the early assessment of myocardial revascularization at a time when other exercise-dependent methods are not feasible, and that a positive test in the early days after surgery indicates patients with a high risk of later developing ischemic events.

Although a role for free radicals in myocardial damage during cardiopulmonary bypass for open heart surgery has been postulated, direct evidence of free radical production as well as consumption of tissue antioxidants such as vitamin E is still lacking. Twenty patients (age 26-66 yr, mean 48) undergoing elective open heart surgery with moderate hypothermia, and cold crystalloid cardioplegia, were studied. Cardiopulmonary bypass time was 61.4 +/- 31.2 min. The specimens of atrial tissue collection before and after cardiopulmonary bypass, were immediately frozen in liquid nitrogen. Mean vitamin E atrial content, measured by reverse phase HPLC, was 355 +/- 249 pmol/mg of dry weight basally, 135 +/- 85 pmol/mg (p0.05) at the end of the ischemic period and 405 +/- 288 pmol/mg after the reperfusion period (p0.01). Microscopic examination of right atrial biopsies ruled out differences in fibrosis or cellular damage as the cause of vitamin E changes. Although a great basal variability in atrial vitamin E content was observed, which was independent of age, sex and clinical status, a reproducible and substantial decrease in atrial vitamin E content after cardiopulmonary bypass occurred (mean reduction 45 +/- 17% and 55 +/- 22%, respectively, after ischemia and after reperfusion). This was directly related to the aorta cross-clamping duration and partially to the minimum temperature achieved. In conclusion, apart from the great variability observed in basal vitamin E tissue content, vitamin E was always reduced during cardiopulmonary bypass, suggesting an oxidative stress on the myocardium during open heart surgery.

Background The aim of the study was to assess the value of Pulsed-wave Doppler tissue imaging (DTI) in assessing diastolic and systolic function in patients with severe aortic value stenosis. Methods Thirty-five patients with aortic stenosis (AS) (valve orifice ≤ 1 cm 2 , mean age 71.8 ± 6.2) and 35 comparable healthy subjects were studied. All subjects performed conventional 2-dimensional Doppler echocardiography and DTI at mitral annulus level. Patients with AS were divided into 2 groups: 16 patients who presented initial signs of HF and a depressed left ventricular systolic funciton (AS I) (EF: 35%-50%) and 19 patients were asymptomatic and had normal left ventricular systolic function (EF > 50%) (ASII). The 16 symptomatic AS patients underwent surgical aortic valve replacement and were examined after 1 year. Results DTI was able to detect abnormalities of systolic and diastolic function in AS: the significantly lower peak S velocity in AS I than in AS II and in controls, both at septum and lateral wall level; the significantly lower peak E velocity in AS I than in AS II and in controls both at septum and lateral wall level; the significantly higher peak A velocity in AS I than in AS II and in controls both at septum and lateral wall level; the significant lower E/A ratio in AS I than in AS II and in controls both at septum and lateral wall level. Conclusion We found a significant inverse correlation between DTI lateral S velocity, DTI peak E velocity, lateral DTI E/A ratio, and AS peak and mean gradient. According to the results of this study we can affirm that DTI parameters surely had an important physiopathological impact in the knowledge of myocardial function in patients with severe aortic stenosis.

Background . Controversy still exists about the choice of aortic prosthesis in elderly patients. This study investigates valve- and anticoagulant-related morbidity and mortality in elderly patients after aortic valve replacement (AVR) with a biologic (BP) or mechanical prosthesis (MP). Methods . Between 1981 and 1995, 355 consecutive patients aged 70 years or older (mean, 74 ± 4 years; range, 70 to 87 years) underwent isolated AVR. There were 222 (63%) replacements with an MP and 133 (37%) with a BP. Mean follow-up was 3.7 ± 2.8 years (range, 3 months to 15 years), with a total follow-up of 1,214 patient-years. Results . Hospital mortality was 7.6% (27 of 355), decreasing to 4.6% in the last 3 years. There were 55 late deaths, 33 in patients with MP and 22 in those with BP. At 10 years there was no significant difference between MP and BP recipients in the actuarial estimates of survival (51% ± 8% versus 33% ± 13%), freedom from valve-related death (82% ± 7% versus 72% ± 12%), and freedom from thromboembolism (84% ± 7% versus 94% ± 3%). In contrast, 10-year freedom from anticoagulant-related hemorrhages was 74% ± 8% for MP and 99% ± 1% for BP ( p = 0.02). Only 1 structural deterioration occurred, in a patient with BP. Conclusions . Satisfactory early results can be obtained in elderly patients after AVR with both MP and BP. The comparable low late survival in the two groups was predominantly influenced by non–valve-related deaths. A higher incidence of anticoagulant-related hemorrhages limits the use of MP in elderly patients. Thus, in this population, BP should be preferred not just on the basis of their expected longer durability, but mainly to avoid the risk of anticoagulant-related hemorrhages.