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G D'Ancona

Publications and source records attributed to G D'Ancona.

54 records · Page 3Linked to original sources
PubMed1997

Six-and-half years' experience with the St. Jude BioImplant porcine prosthesis.

BACKGROUND AND AIMS OF THE STUDY: In this study, we reviewed our experience in heart valve replacement with the St. Jude BioImplant heart valve, which is a low-profile, low-pressure glutaraldehyde-fixed porcine prosthesis mounted on a flexible Delrin stent. METHODS: During the period May 1989-January 1996, 117 patients were implanted with 132 BioImplant prostheses; three patients were lost to follow up and excluded from the series. Mean age was 67.5 +/- 9.8 years (range: 19 to 82 years); myocardial revascularization was performed in 22 (19.3%) patients. In-hospital mortality rate was 6% (7/117 patients). By January 1996, 114 patients (53 males, 61 females), in whom 59 aortic, 35 mitral, 15 mitro-aortic and five tricuspid prostheses had been implanted, were eligible for the analysis. Mean follow up was 40.4 +/- 21.7 months (range: 1 to 76 months). RESULTS: The survival probability of survivors was 72.1 +/- 6.5 at 77 months. Seventeen patients died during follow-up. The mean NYHA class improved from 3.1 +/- 0.6 preoperatively to 1.4 +/- 0.6 postoperatively. The freedom probabilities were respectively 89.5 +/- 5.3% from thromboembolism, 93.2 +/- 3.7% from infective endocarditis, 84.5 +/- 10.3% from structural dysfunction, 99.1 +/- 0.9% from non-structural dysfunction, and 80.1 +/- 10.2% from reoperation. The freedom probability for valve-related events was respectively 75.3 +/- 12.3%, 98.0 +/- 1.9% and 67.2 +/- 17.2% for patients who underwent mitral, aortic and mitro-aortic heart valve replacement (p = 0.05 comparing only patients who underwent mitral or aortic replacement); moreover the freedom probability from valve-related events was 71.6 +/- 11.2% in patients aged < or = 65 years and 90.2 +/- 6.6% in patients aged > 65 years (p = 0.006). CONCLUSIONS: The BioImplant heart valve, in our experience, seems to be a valuable device which shows a mid-term performance similar to that of other porcine prostheses.

Adult↗
PubMed1997

[Transmyocardial laser revascularization in patients with peripheral coronary atherosclerosis. Indications and preliminary results].

BACKGROUND: Surgical intervention for coronary artery disease (CAD) is determined by the viability of coronary artery branches. When peripheral coronary artery disease is present, conventional bypass grafting is not suitable. Research has recently been done on alternative methods such as transmyocardial laser revascularization (TMLR). TMLR works through the vascular connections that are present between the cardiac chambers and the myocardial muscle in the human heart. The creation of 1-mm transmural cardiotomies through a CO2 laser should improve myocardial perfusion. METHODS: From February to June of 1996, twelve patients (9 males and 3 females with a mean age of 67.8 +/- 4.6) with CAD (mean n0 of diseased vessels 2.7), angina (mean CCS class 3.5 +/- 0.5), mean ejection fraction 47.8% and viable ischemic myocardium on scintiscan in segments without graftable coronary branches, underwent TMLR at our institute. Nine of the 12 patients also underwent associated CABG (mean number of anastomoses per patient: 2.5). Cardiopulmonary bypass was never used, since coronary anastomoses and laser cardiotomies were performed on the beating heart. RESULTS: Perioperative mortality was 2/12 (16.6%). Postoperative inotropic support and diuretic therapy was required in most cases. At a mean follow-up period of 4.2 months, all remaining patients are still alive: 5/10 are angina-free (CCS 0), 4/10 are in CCS class 1 and 1/10 is in CCS class 2 (mean 0.6 +/- 0.7). CONCLUSIONS: We believe that TMLR could be considered an effective mean to treat symptomatic myocardial ischemic disease in which coronary bypass grafting is not suitable. During the immediate postoperative period, contractile myocardial dysfunction occurs in a high percentage of patients treated using TMLR and consequently it would be worthwhile to invest in further research.

Aged↗
PubMed1997

Timing for surgical treatment in native infective endocarditis. A seven-year experience.

BACKGROUND: Early surgical intervention in infective endocarditis is performed only when there is persistence of sepsis, hemodynamic instability or when arterial embolism has occurred, otherwise a 4-week antibiotic therapy before surgery is considered necessary. Our 7-year experience in the surgical treatment of native endocarditis in 28 patients, is here revised focusing on the timing of surgery. METHODS: Patients were retrospectively divided into group A (n. 16) with blood cultures that became negative before surgery and group B (n. 11) with blood cultures positive at the time of urgent surgery. One patient with constantly negative blood cultures was not assigned to any group. In group A antibiotic therapy was administered until 3 consecutive blood cultures became negative and the patients were then operated on the basis of echocardiographic findings after a mean duration of antibiotic therapy of 17.4 +/- 6.3 days. RESULTS: Twenty-six patients out of 28 underwent replacement of the infected valve (mechanical bileaflets in 16 patients, porcine stented in 7 and porcine stentless in 3). Valve repair was performed in 2 patients. Overall operative mortality was) 7.1% (2/28); death occurred in 2 patients of group B, operated on for cardiogenic shock. Two/26 patients died (1 acute renal failure and 1 stroke) at a mean follow-up of 32.5 +/- 24.8 (range 3-95) months. CONCLUSIONS: Patients who underwent surgery for infective endocarditis after blood culture negativization showed no mortality and no recurrence of disease even if a 4 weeks antibiotic course was not completed. This experience suggests that earlier operations can be performed safely, lowering the incidence of hemodynamic impairment and arterial embolism.

Endocarditis, Bacterial↗
PubMed1996

[Emergency surgical revascularization in acute myocardial infarct. The preliminary results of a prospective study].

In this paper we describe 1-year experience with a perspective operative protocol of emergency myocardial revascularization in extensive acute myocardial infarction (AMI). Entry criteria were: age < 75 years; anterior AMI with ST segment elevation > 4 leads, infero-postero-lateral or inferior and right ventricular AMI, within 6 hours from symptom onset. After coronary arteriography, an emergency staff, composed by cardiologists and cardiac surgeons, addresses the patients to coronary artery bypass grafting (CABG) or to percutaneous transluminal coronary angioplasty (PTCA). From November 1994 to November 1995, 35 patients were enrolled: 19 (mean age 54.3 +/- 9.7 years) underwent CABG and 16 were treated with PTCA. Myocardial protection was such as to restore energetic substrates and to prevent reperfusion injury: surgical technique consisted of antegrade-retrograde substrate-enriched blood cardioplegic solution delivery, early cardioplegic delivery on the infarcting area via a saphenous graft, retrograde controlled reperfusion before aortic unclamping and then prolonged reperfusion of the infarcted myocardium. In 8 patients (mean age 50.9 +/- 8.6 years), with anterior AMI and stable hemodynamics, a left internal thoracic artery graft was used, performing the prolonged controlled reperfusion retrogradely before aortic unclamping. In hospital death occurred in 1/19 (5.3%) patients because of cerebral hemorrhage. At a mean follow-up of 5.1 +/- 3.7 months 17 patients (94.4%) were in NYHA functional class I-II and 1 patient (5.6%) complained of effort angina, that was well controlled with medical therapy. Left ventricular ejection fraction calculated by echocardiography preoperatively, before discharge and at follow-up was respectively 39.3 +/- 12.7, 43.1 +/- 8.9 and 43.4 +/- 9.0%. In the last 8 consecutive patients thermodilution and transesophageal echocardiography monitoring were performed preoperatively and 12 hours after CABG: in all cases ejection fraction and cardiac index increased after CABG, from 42.2 +/- 13.5 to 48.6 +/- 14.3% (p = 0.01) and from 2.8 +/- 0.5 to 3.4 +/- 0.6 l/min/m2 (p = 0.005), respectively. The preliminary results show the effectiveness of this perspective protocol in the management of critically ill patients with extensive AMI.

Clinical Protocols↗
PubMed1990

The coelomocytes of Holothuria polii (Echinodermata). II. Cytochemical staining properties.

Histochemical studies by traditional staining methods for lipids, mucopolysaccharides and proteins and histoenzymatic reactions typical of lysosomal activity were carried out on the principal coelomocyte types of Holothuria polii. These are considered to be the cellular contigent of the immune response, and in Holothuria polii, they probably take part also in clotting events.

Animals↗
PubMed1988

Morphological and biochemical effects of glucocorticoids in chick embryo hepatocytes during development.

The administration in ovo of hydrocortisone-21-phosphate caused, in chick embryo liver, a reduction of the number of hepatocytes which can be isolated from 1 mg dry weight of liver and a marked increase of their size. Moreover, the treatment diminished the incorporation of thymidine into acid-insoluble fraction in these cells whilst it augmented the content of protein, RNA, DNA and the level of thymidine kinase/cell. These effects were highest at 8-10 days, then declined with the age, disappearing after 18th day of incubation. Similar effects were obtained by injecting other glucocorticoids or ACTH. Combined treatment with metopirone abolished the effects found with ACTH, but did not modify the action of hydrocortisone. These findings suggest that glucocorticoids interfere with the proliferative cycle of hepatocytes by inhibiting the mitotic phase and favouring the production of abnormally large cells.

Adrenocorticotropic Hormone↗
PubMed1987

Influence of hydrocortisone on chick embryo retina development.

Treatment of chick embryos in ovo with hydrocortisone-21-phosphate (a single dose of 150 micrograms) caused a marked reduction of retinal thymidine kinase activity 24 h later. The inhibitory effect was highest (65-70%) in 8-10-day-old embryos and declined with age, disappearing after day 15. It was accompanied by a reduction in thickness of the retinal layers. Adrenocorticotropic hormone (ACTH) treatment (10 micrograms daily for 2 days) also produced an age-dependent inhibitory effect on retinal thymidine kinase, whereas treatment with a single dose of 200 micrograms of metopirone, a compound that prevents the 11 beta-hydroxylation of steroid molecules in the adrenal glands, impeded the decrease in thymidine kinase activity that normally occurs in chick embryo retina after day 9 of development. In addition, metopirone prevented the inhibition exerted by ACTH on thymidine kinase activity but had no effect on the action of hydrocortisone.

Adrenocorticotropic Hormone↗
PubMedDate not supplied

Techniques of exposure and stabilization in off-pump coronary artery bypass graft.

Recent advances in techniques of coronary artery exposure and myocardial stabilization in off-pump myocardial revascularization have provided cardiac surgeons with a wide variety of new devices and techniques. Until recently, the main obstacle to performing complete myocardial revascularization without using cardiopulmonary bypass (CPB) has been the technical difficulties of exposing and stabilizing coronary targets, especially those located on the lateral and inferior wall of the heart. The extraordinary cardiac tolerance to nonconstrictive anterior elevation and lateral displacement, however, has allowed the development of new strategies of coronary exposure. These advances, in combination with the development of new techniques of mechanical myocardial stabilization, have impacted on the feasibility and safety with which coronary anastomoses on the beating heart can be constructed. The aim of this article is to describe the technical aspects involved in off-pump coronary revascularization, focusing primarily on the most recent strategies of cardiac elevation and coronary exposure, the various techniques of myocardial stabilization, and some of the technical details of constructing distal anastomoses on the beating heart.

Anastomosis, Surgical↗
PubMedDate not supplied

Reoperative grafting of the LAD system using the LAST approach: technical details.

In patients in whom the left internal mammary artery (LIMA) has been previously utilized, reoperative grafting of the left anterior descending (LAD) or diagonal coronary arteries can be performed through a left anterior small thoracotomy (LAST) approach, utilizing the subclavian artery as inflow source. In such cases, however, the left upper lobe of the lung and the lingula may exert unwanted traction on the newly constructed coronary graft. Herein, we describe a detail of technique that eliminates this inconvenience.

Coronary Artery Bypass↗
PubMedDate not supplied

Hemodynamic effects of elevation and stabilization of the heart during off-pump coronary surgery.

BACKGROUND: Coronary artery bypass grafting (CABG) surgery is now being performed without the use of cardiopulmonary bypass (CPB). To achieve complete myocardial revascularization off-CPB, a technique has been developed to expose target coronary arteries while hemodynamics are maintained. METHODS: Complete myocardial revascularization was performed in 18 consecutive patients. Exposure of target coronary arteries was achieved by a "single-suture" technique, placed in the oblique sinus of the pericardium. Traction on the suture elevates and rotates the heart, thereby exposing all target coronary arteries. Cardiac index (CI) and intracardiac pressures were measured with a Swan-Ganz catheter during the different phases of the operation. RESULTS: All patients were successfully operated on without CPB. There were no postoperative complications or deaths. There were no major hemodynamic changes during the different stages of the operation; in other words, CI was unchanged during elevation of the heart and snaring of the main coronary branches. Pulmonary artery wedge pressure (PAWP) increased markedly during occlusion and stabilization of the circumflex coronary artery (p < 0.05). A marked increase in CI and cardiac output (CO) from baseline values was also recorded before chest closure (p < 0.05). CONCLUSION: Complete myocardial revascularization can be achieved safely without CPB. The single-suture technique allows for exposure of all target coronary arteries without hemodynamic compromise.

Cardiopulmonary Bypass↗
PubMedDate not supplied

Myocardial revascularization of the beating heart in high-risk patients.

OBJECTIVE: Myocardial revascularization without cardiopulmonary bypass (CPB) has been proposed as an alternative technique in patients at high risk for conventional coronary artery bypass grafting (CABG). The purpose of this article is to evaluate the potential benefit of such an approach. METHODS: We retrospectively evaluated the perioperative results of off-pump CABG (OPCAB) performed from January 1995 to December 1999. Patients were divided into three groups on the basis of their preoperative risk factors: age greater than 80 years, reoperative CABG, and left ventricular ejection fraction percentage (LVEF%) less than 40%. The three subgroups were compared with patients operated on-CPB (ONCAB) during the same period of time. A total of 172 octogenarians had ONCAB versus 97 OPCAB, 307 reoperations were ONCAB versus 274 OPCAB, and 514 patients with LVEF% less than 40% were operated ONCAB versus 220 OPCAB. RESULTS: Preoperative comorbidities were homogeneously distributed in the OPCAB and ONCAB groups. More extensive coronary artery disease was found in the ONCAB groups. A trend for a lower number of perioperative complications was reported in the OPCAB groups. Freedom from overall complications was significantly higher (p < 0.005) in the OPCAB group. Actual mortality rates in the OPCAB and ONCAB groups were comparable (p = NS). CONCLUSIONS: CABG can be performed safely without CPB in patients with a high preoperative risk profile. Freedom from perioperative complications is markedly higher when the OPCAB approach is utilized.

Aged↗
PubMedDate not supplied

Use of the Internet by patients before and after cardiac surgery: telephone survey.

BACKGROUND: Little is known about to what extent patients who underwent medical treatment access the Internet and whether they benefit from consulting the Internet. OBJECTIVE: To understand if cardiopathic patients use the Internet for health-related information and whether they find retrieved information understandable and useful. METHODS: Telephone interviews, using a semi-structured questionnaire, were conducted with 82 patients who had undergone off-pump coronary-artery bypass grafting at the Center for Less Invasive and Robotic Heart Surgery in Buffalo, New York, USA. Study design was multidisciplinary, combining expertise of medical and communication science. Sources of medical information were identified (doctor, Internet, magazines, newspapers, television, radio, family members). Accessibility, quality, and readability of Internet medical information from the patients point of view were investigated. RESULTS: Out of 82 patients, 35 (35/82, 42.7%) were Internet users. Internet users had a significantly higher education level than Internet non-users (college education: 42.9% of users, 10.6% of non-users; P <.001). Among the Internet users, 18 (18/35, 51.4%) had used the Internet for retrieving medical information; 17 (17/35, 48.6%) had not. No statistically significant differences in demographic data were found when comparing these 2 sub-groups of patients. Family-members involvement was high (15/18, 83.3%). Internet medical information was rated helpful in most cases; readability was acceptable for only 3 patients (3/18, 16.7%). To improve on-line medical information, all patients interviewed suggested sites designed by their physicians. CONCLUSIONS: Although 1 in 5 patients in our sample has used the Internet to retrieve medical information, the majority of them experiences difficulties comprehending the information retrieved. Health-care providers should provide Internet medical information that is adequate for the non-medical public's needs.

Cardiac Care Facilities↗
PubMedDate not supplied

Use of the "single suture" technique to expose the anterior surface of the heart.

The "single suture" technique, which consists of placing a suture in the oblique sinus of the posterior pericardium and connecting it to a vaginal tape, is commonly adopted in off-pump coronary artery revascularization to obtain elevation of the heart and coronary artery exposure. This report describes the use of this technique to expose the anterior wall of the heart in the setting of ventricular aneurysm repair.

Heart Aneurysm↗