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71.
ObjectivesThe aim of this study was to define predictors of prosthesis-patient mismatch (PPM) and its impact on mortality after transcatheter aortic valve replacement (TAVR) with self-expandable valves (SEVs) in patients with small annuli.BackgroundTAVR seems to reduce the risk for PPM compared with surgical aortic valve replacement, especially in patients with small aortic annuli. Nevertheless, predictors and impact of PPM in this population have not been clarified yet.MethodsPredictors of PPM and all-cause mortality were investigated using multivariable logistic regression analysis from the cohort of the TAVI-SMALL (International Multicenter Registry to Evaluate the Performance of Self-Expandable Valves in Small Aortic Annuli) registry, which included patients with severe aortic stenosis and small annuli (annular perimeter <72 mm or area <400 mm2 on computed tomography) treated with transcatheter SEVs: 445 patients with (n = 129) and without (n = 316) PPM were enrolled.ResultsIntra-annular valves conferred increased risk for PPM (odds ratio [OR]: 2.36; 95% confidence interval [CI]: 1.16 to 4.81), while post-dilation (OR: 0.46; 95% CI: 0.25–0.84) and valve oversizing (OR: 0.53; 95% CI: 0.28–1.00) seemed to protect against PPM occurrence. At a median follow-up of 354 days, patients with severe PPM, but not those with moderate PPM, had a higher all-cause mortality rate compared with those without PPM (log-rank p = 0.008). Multivariable Cox regression confirmed severe PPM as an independent predictor of all-cause mortality (hazard ratio: 4.27; 95% CI: 1.34 to 13.6).ConclusionsAmong patients with aortic stenosis and small aortic annuli undergoing transcatheter SEV implantation, use of intra-annular valves yielded higher risk for PPM; conversely, post-dilation and valve oversizing protected against PPM occurrence. Severe PPM was independently associated with all-cause mortality.  相似文献   
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BACKGROUND: Composite arterial grafts are presently being used ever more frequently in coronary bypass surgery. We assessed the composite radial artery and in situ left internal thoracic artery Y-graft by means of transthoracic echo-Doppler and myocardial perfusion scintigraphy (MPS). METHODS: In 53 patients who underwent complete myocardial revascularization using only this composite arterial graft, good transthoracic echographic images and pulsed Doppler signals of the Y-graft main stem were obtained at rest and early after standard exercise; the echographic parameters were measured. Stress/rest MPS was the gold standard for residual myocardial ischemia. The patients with negative MPS were divided into groups according to the number of coronary vessels grafted and their history of preoperative myocardial infarction. RESULTS: The diastolic-to-systolic ratio of the peak velocities and velocity-time integrals both at rest and after stress, and the stress-to-rest ratio of the diastolic peak velocities and diastolic velocity-time integrals in the negative MPS patients were significantly greater than in the 6 positive MPS patients. However, the restricted number of positive MPS cases limits the power of this statistical analysis. The stress-to-rest ratio of the diastolic velocity-time integrals in the patients with three grafted coronary vessels (median 2.3) and in those without preoperative myocardial infarction (median 2.1) were respectively greater than in the patients with two vessels grafted (median 1.7, p < 0.0001) and those with preoperative myocardial infarction (median 1.8, p = 0.0048). CONCLUSIONS: Dynamic assessment with transthoracic echo-Doppler of a composite arterial graft including the in situ left internal thoracic artery correlates with MPS. In patients with negative MPS, transthoracic echo-Doppler correlates with the myocardial demand.  相似文献   
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Objective—To assess prevalence and type of non-atherosclerotic coronary artery disease in young people (≤35 years) who died suddenly.

Design—A necropsy study of 150 consecutive cases of sudden death (that is, within 6 h of the onset of symptoms).

Results—Death was attributed to coronary artery disease in 48 cases: in 16 (33%) of them the disease was non-atherosclerotic. Twelve subjects (eight males and four females, age range 2–35 years, mean 24·2) had congenital anomalies: a deep intramyocardial course in six, origin from the wrong sinus in three, and ostial obstructions in three. Sudden death was the first manifestation of disease in six cases. The other six had a history of palpitation or syncope or both. An electrocardiogram was available in five cases and showed ventricular arrhythmias in four; none had angina pectoris. Stress testing was available in two cases: neither showed any effort-dependent ST-T abnormalities. In six cases sudden death was related to physical exercise. Acquired non-atherosclerotic coronary artery disease was found in four cases: spontaneous coronary dissection in three previously symptom free patients and Kawasaki coronary arteritis in one child who had had acute myocardial infarction.

Conclusion—One third of the cases of fatal coronary artery disease were non-atherosclerotic with coronary artery anomalies being the most frequent form. Coronary artery anomalies should be suspected in young patients who have symptoms of ventricular arrhythmias without any overt signs and symptoms of ischaemia.

  相似文献   
76.
To analyze the state of health care for patients with myocardial infarction, questionnaires were sent to 191 Italian general hospital and university cardiological departments equipped with an intensive coronary care unit (ICCU). A total of 139 returned the questionnaire (72.7%), of which 138 were usefully completed. The mean number of beds per ICCU is 5.7 and still today 14% of the ICCU's transfer their patients to a medical department. The mean time to admission is 7 hours. In the acute phase, rehabilitation is begun in 49% of the ICCU; mobilization and hospitalization times are shorter than in 1978. The most widely employed pharmacological treatment in the acute phase is the glucose-potassium-insulin infusion (74%). Prior to discharge, 16% of the institutions obtain an exercise test, 74% an echocardiogram and 42% a dynamic ECG. Health education programs, on the other hand, are very poor: only a few Centers provide educational material. In the case of recurrent chest pain, 81% of the institutions advise the patients to take nitroglycerin, and 67% with the patients to report to the hospital. Eighty-nine percent of the Centers carry out follow-up tests on all their patients 1 month after discharge. Calcium antagonists and nitrates are prescribed on discharge by one half of the departments. In the post-infarction period an effort test is performed in 54% of Centers; coronary angiography is carried out on the youngest patients in 9% of Centers; in 30% of Centers, coronary angiography is only performed in patients with severe symptoms. Sixty-five institutions administer their own rehabilitation programs, while 35 send their patients to other institutions.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
77.
One of the causes for percutaneous transluminal coronary angioplasty (PTCA) failure is the inability to cross the lesion with the balloon catheter after guidewire positioning. The Europass? coronary angioplasty catheter is a monorail Duralyn? balloon catheter developed to enhance lesion crossability and to overcome this limitation. This system was evaluated in 50 patients in which target lesions were chronic total coronary occlusions (12 cases) or stenoses that could not be reached or crossed by other new monorail balloon catheters. Overall procedural success was obtained in 49/50 patients (98%), using a single Europass? balloon catheter in 46/50 patients (92%), with no in-hospital complications. Its low profile, small distal shaft, and excellent trackability allowed successful angioplasty in cases where other catheters failed. This balloon catheter represents a significant advance in angioplasty technology and can be considered as a first-choice device for a safe and expeditious single-operator procedure. © Wiley-Liss, Inc.  相似文献   
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First-generation drug-eluting stents (DES) have been associated with impaired localized coronary vasomotion and delayed endothelialization. We aimed to compare coronary vasomotion after implantation of a newer-generation everolimus-eluting stent (EES), with a first-generation paclitaxel-eluting stent (PES). Coronary vasomotion was studied in 19 patients with EES and 13 with PES. Vasomotor response was measured proximally and distally to the stent and in a remote vessel (reference segment). Quantitative coronary angiography was performed offline. Endothelium independent vasomotion did not differ significantly between the two groups. EES showed significant vasodilatation while PES showed vasoconstriction at both proximal (+4.5?±?3.6 vs ?4.2?±?6.9, p?<?0.001) and distal (+4.6?±?7.9 vs ?4.8?±?9.3, p?=?0.003) segments. The reference segment did not show any significant difference in vasodilatation between the two groups (+9.8?±?6.4 vs +7.2?±?5.2, p?=?0.17). Endothelium-dependent vasomotion at adjacent stent segments is relatively preserved after EES implantation while vasoconstriction was observed after PES implantation.  相似文献   
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