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A M Calafiore

Publications and source records attributed to A M Calafiore.

At least 37 records · Page 2Linked to original sources
PubMed1999

Integrated left anterior small thoracotomy and angioplasty for coronary artery revascularization.

BACKGROUND: The minimal access surgical technique of a left anterior small thoracotomy (LAST) for coronary artery bypass grafting is now well established. This procedure however, does not allow multivessel revascularization. We present our early experience of an integrated approach using LAST and percutaneous transluminal coronary angioplasty (PTCA), either staged or simultaneous. METHODS: Eighteen patients (14 men and 4 women), mean age 63 (range 35-87 years) were treated. Four patients underwent simultaneous LAST and PTCA revascularization. The remaining 14 patients were first treated with the LAST procedure, followed 1-3 days later by angioplasty. Angiographic assessment was carried out before PTCA and at 6 months after. RESULTS: The 14 patients who underwent the staged procedure all had patent left internal mammary artery/left anterior descending coronary artery grafts. Angioplasty was performed on 21 vessels (10 stented) with good early angiographic results. All patients were extubated early, mean intensive care stay was 14.7 + 9.4 hours, mean hospital stay was 5 + 1.5 days. All patients were symptom free at 18 months follow-up. CONCLUSIONS: Staged LAST and angioplasty is a safe and effective approach suitable for patients in whom there are contraindications to the use of extracorporeal circulation. The simultaneous approach is limited by the risk of bleeding associated with the use of anticoagulation when coronary stenting is required.

Adult↗
PubMed1999

Angiographic anatomy of the grafted left internal mammary artery.

BACKGROUND: The hypothesis that persistence of undivided branches is a common finding after myocardial revascularization using the left internal mammary artery was explored. METHODS: Three hundred seven consecutive postoperative angiographies of the left internal mammary artery were considered. Seven were excluded because of occlusion or malfunction of the conduit or the anastomosis. Of the remaining 300, 150 were harvested through a left anterior small thoracotomy (group A) and 150 through a median sternotomy (group B). The persistence of undivided branches was recorded for each group. RESULTS: Common origin with other branches of the subclavian artery was present in 55 patients in group A and 54 in group B (p = not significant); the persistence of lateral costal branch was also equally distributed in both groups (15 and 17; p = not significant). The first intercostal artery was present in 5 patients in group A and in none in group B (p = not significant). Branches of 1 mm or more were more frequent in group A (34 versus 4, p < 0.001), as well as branches of less than 1 mm (140 versus 67; p < 0.001). Only 2 patients in group A had no branches versus 48 patients in group B (p < 0.001). CONCLUSIONS: Common origin with other branches of the subclavian artery and persistence of the lateral costal branch are common aspects in the angiographic anatomy of the grafted left internal mammary artery. Moreover, new branches, sometimes wider than 1 mm, develop with time. These findings are independent from the harvesting technique, the left anterior small thoracotomy, or the median sternotomy. If flow competition between the coronary and noncoronary territories was a reality, coronary artery grafting with the left internal mammary artery would be unsuccessful since the beginning.

Coronary Angiography↗
PubMed1999

Off or on bypass: what is the safety threshold?

BACKGROUND: To identify the technical profile of the patients operated on without cardiopulmonary bypass (CPB) and the benefit of the procedure. METHODS: From May 21, 1997, to December 31, 1998, 785 patients had coronary artery bypass grafting through a median sternotomy (group A: 472 without CPB; group B: 290 with CPB; group C: 23 converted). Technical aspects, mortality rate, cerebrovascular accident (CVA) incidence (crude and risk-adjusted), and incidence of major complications were recorded. RESULTS: Patients without CPB had mainly one to three grafts and one- or two-vessel disease. Multiple arterial grafting was not a limit, whereas sequential grafting was. Group A had lower complications rates, shorter intensive care unit and postoperative in hospital stays, and lower transfusion rates. Mortality rates and CVA incidence (crude and risk-adjusted) were similar in both groups and in each subgroup considered. In group A, a lower complications rate was present in some patients (aged greater than 70 years, female, with unstable angina). Group C showed higher mortality and complications rates. Failure of revascularization showed no difference between groups. CONCLUSIONS: Primary endpoints are not affected by the surgical strategy, whereas some of the secondary endpoints are. However, patients in group A experienced fewer complications. Both techniques can give satisfying results and must be applied according to the surgeon's preference.

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PubMed1999

Current results in off pump surgery.

OBJECTIVE: We reviewed our experience with myocardial revascularization without cardiopulmonary by-pass (CPB) to evaluate early- and mid-term results compared with those obtained using CPB. METHODS: From May 21, 1997 to November 1998, 747 patients had isolated myocardial revascularization, 480 without CPB (Group A) and 267 with CPB (Group B). Exposure of the target vessels was obtained with four slings (two passed through the transverse sinus and two behind the inferior vena cava) and four deep pericardial sutures on the mobile pericardium around the left atrium (Lima stitches). The number of anastomoses/patient (when two or more conduits were used) was higher in Group B (3.1 +/- 1.0 vs 2.6 +/- 0.7, P < 0.001). More marginal branches were grafted in Group A (258 vs 239), but the percentage was higher in Group B (P < 0.001). Crude and risk adjusted mortality was similar in both groups, as well as cerebrovascular accident (CVA) and acute myocardial infarction incidences. Patients in Group A woke earlier, had less inotropes, lower creatinkinase myocardial band (CK-MB) peak, lower bleeding and less transfusion, shorter Intensive Care Unit (ICU) and postoperative stay in hospital than patients in Group B. 266 anastomoses were checked; of these 98.5% were patent and 97.0% were patent and not restrictive. CONCLUSIONS: Myocardial revascularization without CPB can provide good early- and mid-term results in selected patients. Primary endpoints (death and acute myocardial infarction) were similarly independent from the technique used. Some of the secondary endpoints were favorable in Group A: however their importance is minor. Even if we feel that some high risk patients with severe comorbidities can benefit from CPB surgery; this aspect is difficult to demonstrate scientifically.

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PubMed1999

Surgical treatment of dilated cardiomyopathy with conventional techniques.

OBJECTIVE: We review our surgical experience using different conventional surgical techniques in the surgical treatment of the dilated cardiomyopathy (DCMP) in non-transplant eligible patients. METHODS: In this series we included patients who fit the following criteria: ejection fraction < 35%; end diastolic volume > or = 110 ml/m2; enlargement of the base of the heart (maximal mitral diameter > or = 22 mm/m2) with functional mitral regurgitation; mitral surgery to be performed in every case. Moreover, two groups were considered. (A) Normal or moderately impaired right ventricular function; PAP < 45 mmHg; elective or semielective surgery. (B) Severely impaired right ventricular function; PAP > or = 45 mmHg; severe organ failure; dependency on IABP and/or inotropes; need of ICU stay. From January 1990 to September 1998, 66 patients underwent isolated mitral valve surgery (n = 30); in the remaining 36 the Batista operation (n = 21) or exclusion of akinetic areas (n = 15) were associated. The etiology was ischemic in 42, idiopathic in 23 and post-valvular in one. RESULTS: When isolated mitral valve surgery was performed, early mortality in group A (n = 22) was 0, in group B (n = 8) 50%. Overall 5-year survival was 70.0 +/- 8.4. in group A 81.8 +/- 8.2, and in group B 37.5 +/- 17.1. When the Batista operation was performed, early mortality in group A (n = 13) was 23.1%, in group B (n = 8) 75%. Overall 2-year survival was 42.9 +/- 10.8 in group A 61.5 +/- 13.5 and in group B 25.0 +/- 15.3. When akinetic areas were excluded, early mortality in group A (n = 11) was 18.2% and in group B (n = 4) 100%. Overall 1-year survival was 53.3 +/- 12.9, in group A 72.7 +/- 13.4. CONCLUSION: Group A patients have better results in every cohort of patients considered. Even if patients selection seems to be the most important variable for early mortality and late survival, isolated mitral valve surgery, when feasible, provides the best early and late results.

Adult↗
PubMed1999

Color duplex scanning for the identification of extracranial atherosclerosis in patients with suspected coronary artery disease.

BACKGROUND: The presence of extracranial artery disease has been used as a predictor of coronary artery disease (CAD). The present study was conducted to test the prevalence of extracranial artery disease among patients with suspected CAD. METHODS: Among candidates for coronary arteriography, 400 consecutive patients (mean age 63 +/- 11 years, 78% males, 22% females) underwent color duplex ultrasound of carotid arteries. RESULTS: Extracranial artery disease was documented in 60 patients (15%), CAD in 309 patients (77%). Patients with extracranial artery disease were significantly older (p < 0.001), smoked a higher amount of pack-years (p < 0.001), showed a higher incidence of diabetes (p < 0.01), hypertension (p < 0.05) and CAD (p < 0.05) when compared to extracranial artery disease-free subjects. Plotting age against extracranial artery disease and CAD distribution, extracranial artery disease occurred later in life than CAD (p < 0.001). The best cut-off point of age for predicting extracranial artery disease was 68 years. Carotid angiography was performed in 114 patients after cardiac catheterization (k = 0.8044 with color duplex scanning). CONCLUSIONS: Extracranial artery disease is frequent among patients undergoing coronary arteriography. Carotid ultrasound screening is useful in older patients.

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PubMed1998

Glutathione-related antioxidant defenses in human atherosclerotic plaques.

BACKGROUND: Oxidative stress, resulting from an antioxidant/prooxidant imbalance, seems to be crucial in atherogenesis. Recent evidence has emerged, however, of a surprisingly high content of low-molecular-weight antioxidants in human atherosclerotic plaques, although other antioxidant systems have not been investigated in these lesions. METHODS AND RESULTS: We studied glutathione-related antioxidant defenses (which play a key role in tissue antioxidant protection) in carotid atherosclerotic plaques of 13 patients subjected to endarterectomy and in normal internal mammary arteries of 13 patients undergoing coronary artery bypass surgery. Selenium-dependent glutathione peroxidase activity was undetectable in the plaques of 7 patients; the other 6 patients with plaques showed a mean enzymatic activity approximately 3.5-fold lower than that of mammary arteries. Glutathione reductase activity was also markedly lower in the plaques than in the arteries. Glutathione transferase instead had comparable activity in the two tissues. Remarkably, 5 of the 7 patients with an undetectable selenium-dependent glutathione peroxidase activity but none of the 6 with a detectable one were characterized by multivascular atherosclerotic involvement (3 patients) or stenosis of the contralateral carotid artery (2 patients). CONCLUSIONS: A weak glutathione-related enzymatic antioxidant shield is present in human atherosclerotic lesions. Although the cause of this phenomenon remains to be determined, the present data suggest that a specific antioxidant/prooxidant imbalance operative in the vascular wall may be involved in atherogenic processes in humans.

Antioxidants↗
PubMed1998

Minimally invasive mammary artery Doppler flow velocity evaluation in minimally invasive coronary operations.

BACKGROUND: Left internal mammary artery Doppler flow velocity assessment during the Azoulay maneuver (patient's legs are passively lifted up and actively maintained by the patient) can increase the information on the anastomosis quality after left internal mammary artery to left anterior descending coronary artery grafting after the left anterior, small thoracotomy operation. METHODS: One hundred patients had an early postoperative angiography and a Doppler flow velocity assessment at rest and during the Azoulay maneuver. Peak and mean systolic velocities, peak and mean diastolic velocities, and peak and mean diastolic to systolic velocity ratios were recorded in all patients. RESULTS: In 95 patients with no restrictive conduit or anastomosis, peak and mean diastolic to systolic velocity ratios increased during the Azoulay maneuver; all but 1 patient showed at least one ratio equal to or greater than 1. In 4 patients with restrictive conduit or anastomosis, peak and mean diastolic to systolic velocity ratios were always less than 1 during the Azoulay maneuver. In the patient with an occluded conduit these ratios were less than 0.6. CONCLUSIONS: Peak and mean diastolic to systolic velocity ratios less than 1 during the Azoulay maneuver are suggestive of conduit or anastomosis malfunction. If we limit the angiographic controls to these patients, it is very likely that a pathologic anastomosis or conduit will not be missed.

Blood Flow Velocity↗
PubMed1998

The LAST operation: techniques and results before and after the stabilization era.

BACKGROUND: Left anterior descending artery stabilization allows performance of left internal mammary artery grafting via a left anterior small thoracotomy on a beating heart. Our surgical experience was reviewed to assess if surgical results have improved as result of specialized instrumentation. METHODS: Of 545 patients who had the left anterior small thoracotomy operation, 261 underwent this procedure for single left anterior descending artery disease. Two groups were considered, before and after the use of specialized instrumentation: group A (n = 93), operated on from November 21, 1994, to April 20, 1996; and group B (n = 168), operated on from April 21, 1996, to December 1997. RESULTS: Early mortality was similar in the two groups. The further revascularization (operation or percutaneous transluminal coronary angioplasty) and the rate of occlusion of the conduit were higher in group A, whereas anastomotic or conduit malfunction was not. Cumulating angiography and Doppler flow evaluation, 92.5% of the anastomoses in group A and 98.8% in group B (p = 0.026) were patent, and 90.3% in group A and 97.6% in group B (p = 0.031) were patent and not restrictive. At 19 months, survival was similar, but the event-free survival was higher in group B. CONCLUSIONS: Both left anterior descending artery stabilization and safer left internal mammary artery harvesting contributed to improve angiographic and clinical results after the left anterior small thoracotomy operation.

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PubMed1998

Midterm results after minimally invasive coronary surgery (LAST operation)

BACKGROUND: Our experience with a left internal thoracic artery graft to the left anterior descending artery via a left anterior small thoracotomy is reviewed to evaluate midterm results. METHODS: From November 1994 to April 1997, four hundred sixty patients were scheduled to undergo a left internal thoracic artery graft to the left anterior descending coronary artery via a left anterior small thoracotomy; 26 of these patients (5.7%) were converted and 434 of them had the operation. Two hundred fourteen patients (49.3%) had isolated disease of the left anterior descending artery, and 220 patients (50.7%) had multiple vessel disease. A sufficient length of the left internal thoracic artery was harvested to reach the left anterior descending artery. RESULTS: Three hundred nine patients (71.2%) underwent extubation by hour 2. Mean intensive care unit stay was 4.2 +/- 4.5 hours; mean postoperative hospital stay was 66 +/- 29 hours; the 30-day mortality rate was 1.1%; the late mortality rate was 1.4%. Eighteen patients underwent reoperation early (< or = 30 days), and eight patients underwent reoperation late (> 30 days) because of conduit/anastomotic malfunction. Four patients underwent reoperation with patent anastomosis for progression of disease (n = 3) or pericarditis (n = 1). Three patients had a percutaneous transluminal coronary angioplasty. Cumulating angiographic and stress Doppler flow assessment results, a patent anastomosis was obtained in 417 patients and a nonrestrictive anastomosis in 404 patients. Twenty-nine months after surgery, survival was 97.1% +/- 0.7% (95% confidence interval 90.5% to 100%) and event-free survival 89.4% +/- 1.2% (95% confidence interval 78.2% to 100%). In the last 190 patients, with our increased experience and better instruments, we obtained a patent anastomosis in 188 patients (98.9%) and a nonrestrictive anastomosis in 185 (97.4%). CONCLUSIONS: Left anterior small thoracotomy gives acceptable midterm results. Incidence of patent and nonrestrictive anastomoses was satisfactory, especially in the most recent part of our experience, when the learning curve ended.

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PubMed1998

Intermittent antegrade hyperkalaemic warm blood cardioplegia supplemented with magnesium prevents myocardial substrate derangement in patients undergoing coronary artery bypass surgery.

OBJECTIVE: The influence of the addition of magnesium on myocardial protection with intermittent antegrade warm blood hyperkalaemic cardioplegia in patients undergoing coronary artery surgery was investigated and compared with intermittent antegrade warm blood hyperkalaemic cardioplegia only. METHODS: Twenty-three patients undergoing primary elective coronary revascularization were randomized to one of two different techniques of myocardial protection. In the first group, myocardial protection was induced using intermittent antegrade warm blood hyperkalaemic cardioplegia. In the second group, the same technique was used except that magnesium was added to the cardioplegia. Intracellular substrates (ATP, lactate and amino acids) were measured in left ventricular biopsies collected 5 min after institution of cardiopulmonary bypass, after 30 min of ischaemic arrest and 20 min after reperfusion. RESULTS: There were no significant changes in the intracellular concentration of ATP or free amino acid pool in biopsies taken at the end of the period of myocardial ischaemia. However, the addition of magnesium prevented the significant increase in the intracellular concentration of lactate seen with intermittent antegrade warm blood hyperkalaemic cardioplegia. Upon reperfusion there was a significant fall in ATP and amino acid concentration when the technique of intermittent antegrade warm blood hyperkalaemic cardioplegia was used but not when magnesium was added to the cardioplegia. CONCLUSIONS: This work shows that intermittent antegrade warm blood hyperkalaemic cardioplegia supplemented with magnesium prevents substrate derangement early after reperfusion.

Adenosine Triphosphate↗
PubMed1998

The secondary alcohol metabolite of doxorubicin irreversibly inactivates aconitase/iron regulatory protein-1 in cytosolic fractions from human myocardium.

Anticancer therapy with doxorubicin (DOX) is limited by severe cardiotoxicity, presumably reflecting the intramyocardial formation of drug metabolites that alter cell constituents and functions. In a previous study, we showed that NADPH-supplemented cytosolic fractions from human myocardial samples can enzymatically reduce a carbonyl group in the side chain of DOX, yielding a secondary alcohol metabolite called doxorubicinol (DOXol). Here we demonstrate that DOXol delocalizes low molecular weight Fe(II) from the [4Fe-4S] cluster of cytoplasmic aconitase. Iron delocalization proceeds through the reoxidation of DOXol to DOX and liberates DOX-Fe(II) complexes as ultimate by-products. Under physiologic conditions, cluster disassembly abolishes aconitase activity and forms an apoprotein that binds to mRNAs, coordinately increasing the synthesis of transferrin receptor but decreasing that of ferritin. Aconitase is thus converted into an iron regulatory protein-1 (IRP-1) that causes iron uptake to prevail over sequestration, forming a pool of free iron that is used for metabolic functions. Conversely, cluster reassembly converts IRP-1 back to aconitase, providing a regulatory mechanism to decrease free iron when it exceeds metabolic requirements. In contrast to these physiologic mechanisms, DOXol-dependent iron release and cluster disassembly not only abolish aconitase activity, but also affect irreversibly the ability of the apoprotein to function as IRP-1 or to reincorporate iron within new Fe-S motifs. This damage is mediated by DOX-Fe(II) complexes and reflects oxidative modifications of -SH residues having the dual role to coordinate cluster assembly and facilitate interactions of IRP-1 with mRNAs. Collectively, these findings describe a novel mechanism of cardiotoxicity, suggesting that intramyocardial formation of DOXol may perturb the homeostatic processes associated with cluster assembly or disassembly and the reversible switch between aconitase and IRP-1. These results may also provide a guideline to design new drugs that mitigate the cardiotoxicity of DOX.

Aconitate Hydratase↗
PubMed1998

Left anterior small thoracotomy (LAST): mid-term results in single vessel disease.

BACKGROUND: Left anterior descending artery grafting using the left internal mammary artery via a left anterior small thoracotomy (LAST) gained new popularity in 1994. We review our experience in 250 of 512 patients who underwent a LAST in single vessel left anterior descending artery disease from November 1994 to October 1997. METHODS: Left anterior descending artery stabilization was obtained pharmacologically and mechanically. Two patients (0.8%) had percutaneous transluminal coronary angioplasty at a mean of 23 +/- 5 days; 172 (68.8%) patients had early postoperative angiography. RESULTS: Eight conduits were occluded (patency rate 95.3%). There was only one late death. Cumulative angiography and Doppler flow evaluation showed that 96.8% of the anastomoses were patent and 95.6% were both patent and nonrestrictive. At a mean follow-up of 16.3 +/- 9.3 months, 9 (3.6%) patients had redo-surgery due to anastomotic/conduit failure and 249 (99.6%) patients were alive and asymptomatic. No patients had acute myocardial infarction. The 35-month actuarial survival rate was 99.6% +/- 0.4%, and the event-free survival rate for the entire experience was 93.7% +/- 1.3%. If only the last 157 patients are considered, at 18 months event-free survival was higher than in the entire group of patients (96.4% +/- 1.4% vs 93.7% +/- 1.3%, p = 0.05). CONCLUSIONS: New instrumentation has made the operation easier and has contributed to its spread, along with increased experience and the end of the learning curve. At the moment we consider the LAST a more anatomical and physiological surgical approach to single vessel coronary disease.

Actuarial Analysis↗
PubMed1998

Recent advances in multivessel coronary grafting without cardiopulmonary bypass.

BACKGROUND: Coronary artery bypass grafting (CABG) without the heart lung machine has been possible for easily accessible targets such as the anterior descending or proximal right coronary. Until now technical difficulty in reaching lateral and inferior wall targets imposed significant barriers to multivessel off-pump grafting. To expand the potential for off-pump CABG the authors have devised new exposure and stabilization techniques suitable for all target vessels. In this report we relate our experience with these new techniques and demonstrate that multivessel coronary bypass can be safely performed without cardiopulmonary bypass (CPB). METHODS: From February 8, 1993 to December 16, 1997 a total of 280 patients underwent myocardial revascularization on the beating heart via median sternotomy. Until May 20, 1997 only patients with high preoperative risk factors for CPB were considered for this approach (Group A; N = 122). After this date any patients with favorable anatomy were included (Group B; N = 158) and were subsequently compared with patients operated on using CPB during the same time interval (Group C; N = 114). In Group B patients lateral and/or inferior wall targets were exposed by means of 4 cloth slings (2 through the transverse sinus and 2 behind the inferior vena cava) and by positioning the patients in Trendelenburg with rightward rotation of the table. Regional stabilization of the target artery was obtained with a commercial stabilizing foot plate. RESULTS: Thirty day hospital mortality was only 2 patients (1.6%) in Group A, 3 patients (1.9%) in Group B, and 3 patients (2.6%) in Group C (NS). Postoperative complications were low in both Group A and B. When Group B was compared with a similar cohort in whom CPB was used (Group C), there were statistically significant improvements in ICU and hospital stay demonstrated when CPB was not used (16.8+/-10.7 vs 26.3+/-38.6 hours respectively; p = 0.007, and 4.1+/-1.5 vs 5.5+/-2.4 days respectively, p<0.001). Angiographic followup was available for 78 patients in Groups A and B with a global patency rate (all grafts) of 98.6%, including a patency rate of 96.7% for 60 grafts to obtuse marginal branches of the circumflex). CONCLUSIONS: Multivessel CABG without CPB is possible with results similar to those obtained with pump-oxygenator support using simple exposure and stabilization techniques.

Adult↗
PubMed1998

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Cardiopulmonary Bypass↗
PubMed1998

Percutaneous coronary angioplasty of radial artery conduits.

The higher long-term patency of internal mammary artery grafts has stimulated the search for alternative conduits in order to achieve a complete arterial myocardial revascularization. Percutaneous angioplasty is often the preferred strategy for the treatment of recurrent ischemia in patients who previously underwent bypass surgery, but there is limited experience in the treatment of arterial grafts. We describe two cases of percutaneous treatment of diseased radial artery (RA) grafts. In the first case, two disarticulated stents were deployed through an RA graft: half stent inside the anastomosis to the left anterior descending (LAD) artery, and half stent in the distal LAD artery. Diffuse spasm of the RA graft, resistant to ic nitrates, was successfully reversed after ic calcium antagonists. Absence of restenosis was confirmed two years later. In the second case, after simultaneous catheterization of both the left coronary artery and RA graft, two long stents were implanted in the LAD artery and a final "reversed" kissing-balloon dilation through the stent struts was performed; four months later the patient showed proximal occlusion of the LAD artery and the stenotic RA distal anastomosis was successfully dilated.

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