Enhancement of non-coronary collateral blood flow from the internal thoracic arteries: the theoretical and practical basis of an alternative method of myocardial blood supply.

Non-coronary collateral blood flow arrives to the heart from mediastinal, bronchial, and pericardial channels. These enter the heart through the pericardial reflections surrounding the pulmonary and systemic veins, as well as from the vasa vasorum of the aorta and the pulmonary artery leading to and from the myocardium. Before the advent of cardiopulmonary bypass surgery, surgical bilateral ligature of the internal thoracic arteries (ITAs) was performed in patients with ischemic heart disease to increase the perfusion pressure within the channels leading to the heart. Nowadays, the occurrence of natural collaterals between coronary and extracardiac arteries including the ITAs, the potential hemodynamic effects of ITA ligation, the potential of ITAs for developing important collateral branches, and the current availability of angiogenic growth factors could pave the way for the development of a new field in cardiovascular research aimed at developing an alternative strategy of myocardial blood supply by means of the surgical and biological enhancement of non-coronary collateral circulation.

[Segmental occlusion of the internal carotid artery with collateral reinjection downstream from the carotid sinus]. / Occlusion segmentaire de l'artère carotide interne avec une réinjection collatérale postbulbaire.

The preoperative evaluation before coronary bypass led to the discovery of complete atheromatous obstruction of the internal carotid artery sinus in a 79-year-old man free of any neurological symptom. Downstream from the carotid sinus, the patency of the internal carotid artery was ensured by a collateral branch fed by the ipsilateral external carotid artery. This exceptional anatomic variation can be explained by a persistent embryonic artery. The recognition of this atypical feature is clinically relevant because surgery may be possible in some cases, while it is not technically feasible in patients with total obstruction.

Recurrence of postoperative aortic fistulas: is there an ideal method of prevention? A case report.

There are very few cases in English literature of recurrent postoperative aortic fistulas (RPAFs). These are neo-communications between the aortic bloodstream and the lumen of contiguous organs which occur after unpredictable periods from surgical treatment of a previous fistula. The supradiaphragmatic aorta may fistulize into the airways, pulmonary circulation, oesophagus, and cardiac chambers; the infradiaphragmatic aorta into the intestine, stomach, and vena cava. According to the etiology, aortic fistulas are categorized as postoperative (or secondary) and spontaneous (or primary), and RPAF may be considered a subgroup of secondary fistulas. They may recur even more times in the same patient, hence the role of prevention is of the utmost importance. The simultaneous respect of different surgical principles is crucial to make the risk of recurrence less likely. Surgical treatment represents a real challenge due to the emergency conditions and redo nature of operations. Mortality rate is very high. In this article, we describe a case of recurrent aorto-duodenal communication, we discuss the principles of prevention both for the supra and infradiaphragmatic aorta, we introduce some modifications to the classic categorization and we present the first RPAF literature review.

Internal thoracic arterial grafts evaluation by multislice CT scan: a preliminary study.

BACKGROUND AND AIM: The internal thoracic artery (ITA) has a better long-term patency than saphenous veins, and anastomosis between ITA and the left anterior descending artery (LAD) represents the "gold-standard" of surgical myocardial revascularization. The aim of this study is to evaluate the multidetector multislice CT Scan (MCTS) as a means of postoperative evaluation of ITA coronary artery bypass grafts. METHODS: Twenty-eight patients having been operated on for coronary artery bypass with ITA during a 6-months period, benefited, 7 days after surgery, from a patency and anastomotic site control of ITA with a MCTS associated with cardiac gating (Light Speed, General Electric, USA). RESULTS: Internal thoracic artery bypasses are visualized perfectly on all their courses, with possibility of 3D reconstructions, showing the relationship between cardiac cavities and the arterial bypasses. The anastomotic site on the LAD was, in selected cases, perfectly visualized. Sequential bypasses with left ITA are well visualized as well as T or Y right-to-left ITA grafts. However, surgical clips create some image artefacts. CONCLUSIONS: The postoperative control of ITAs are possible by MCTS with a satisfactory resolution. This makes it possible to check the patency of ITAs, their course on the heart surface, and the location and quality of anastomosis with a noninvasive reproductive method.

Surgical repair for degenerative and rheumatic mitral valve disease. Operative and mid-term results.

BACKGROUND: Non randomized studies suggest that mitral valve repair for rheumatic disease is technically more difficult than repair for degenerative disease, and that operative and late results are worse. New surgical techniques have been developed in our and other institutes during the last 5 years, and this moved us to review the experience with these two pathologies and to compare the operative and mid-term METHODS: From March 1996 to September 1997, 66 patients underwent primary mitral valve repair for treatment of degenerative or rheumatic disease. Fifty-two patients (79%) were in the former group (group A) and 14 in the latter (group B). Surgery was performed by 2 experienced cardiac surgeons. A new technique to calculate the exact artificial chordae length was introduced. In 2 cases, tricuspid autografts were transposed to mitral position and reinforced with artificial chordae. Patients were followed both clinically and echocardiographically. The follow-up data were collected in a 1-month period (May 2000). The average clinical follow-up was 3.1+/-0.9 years (range 1.7 to 4.2 years) while the average echocardiographic follow-up was 2.7+/-0.7 years (range 9 months to 4 years). All values were expressed by means of the average and standard deviation. chi(2) and Student's "t"-test were used to analyze the significance between variables. The Kaplan-Meyer method was used for actuarial statistics. RESULTS: There were no operative deaths in either group. In group A, 1 patient underwent a second surgical repair 1 week later, successfully. In group B no patients underwent reoperation within 30 days or during the initial hospitalization. At follow-up of group A there were the following events: deaths from cancer (n=2), endocarditis (n=1), aortic dissection (n=1). At follow-up of group B there were mitral valve replacement (1 year after first operation, n=1), Ross procedure (n=1), ischemic heart failure (n=1). Among the remaining 62 patients followed, 32 were in NYHA class I, 15 in class II, 3 in class III, and none in class IV, in group A. In group B, 7 patients were in class I, 4 in class II, 1 in class III and none in class IV (p=ns). In group A mitral regurgitation was absent in 23 patients, mild in 21, moderate in 6, while in group B it was absent in 4, mild in 6, and moderate in 2 (p=ns). In both groups there were no cases of severe insufficiency. The mean gradient was 1.1+/-1.7 mmHg in group A (median=0), and 2.4+/-3.1 mmHg in group B (median=0), (p=ns). No case of systolic anterior movement was seen at mid-term. The event free-survival rate was 92.8% in group A and 92.3% in B. CONCLUSIONS: Perfecting and innovation of surgical techniques make possible nowadays to reach good and equivalent operative and mid-term results in both pathologies.

Troponin I release after CABG surgery using two different strategies of myocardial protection and systemic perfusion.

BACKGROUND: Controversies still exist over the optimal temperature for blood cardioplegia and systemic perfusion. This study investigates the effect of temperature of blood cardioplegia and systemic perfusion on the release of troponin I and other biochemical markers. METHODS: One hundred and fifty-four consecutive patients were randomly assigned to one of two cardioplegic and systemic perfusion strategies of cold blood cardioplegia with moderate systemic hypothermia (27 degrees C) or tepid blood cardioplegia with mild systemic hypothermia (33 degrees C). Cardiac troponin I and other biochemical markers were measured at baseline, at the end of surgery, at 12 hours and daily thereafter. A two-way ANCOVA for repeated measure was performed to test the effect of cardioplegia on enzyme release independently of variables that were different between the two groups. RESULTS: The time course of dismission of troponin I, creatine kinase MB, and lactate dehydrogenase were significantly lower with tepid blood cardioplegia and mild systemic perfusion independently of the number of distal anastomoses, CPB time, cross clamp time or total volume of cardioplegia. There were no differences between the two groups in the release of total creatine kinase, aspartate transaminase and alanine transferase. CONCLUSIONS: Both strategies of myocardial protection and systemic perfusion guarantee subclinical minor myocardial damage. The strategy of tepid whole blood cardioplegia and mild systemic hypothermia seems to preserve myocardium better than whole blood cold cardioplegia.

A review of aortopulmonary fistulas in aortic dissection.

Aortopulmonary fistula is an exceedingly rare complication of aortic dissection. Only 4 cases in acute dissection and 8 cases in the chronic one have been published previously. We report the thirteenth case and a review of the literature. A man underwent an operation for type A aortic dissection. At surgery, a fistula was discovered between the false lumen and the main pulmonary artery, although the preoperative investigations did not suggest such a complication.

Unusual origin and fistulization of an aortic pseudoaneurysm: "off-pump" surgical repair.

Aortic pseudoaneurysm is an unusual complication of cardiac operations. The origin depends on the site of arterial wall disruption. Rupture into the right side of the bronchial tree is an exceedingly rare evolution. Repair is commonly performed using cardiopulmonary bypass. In our report a male patient underwent two procedures for aortic dissection, and 6 months after the second operation massive hemoptysis appeared abruptly. A false aneurysm rose from a graft-to-graft anastomotic site and ruptured into a segmental bronchus of the right upper lobe. Repair was performed without cardiopulmonary bypass.

Atrial septal defect associated with Albright's hereditary osteodystrophy and other anomalies: a clinical case.

A 36 year-old woman with a history of asthenia and palpitations was admitted to the Cardiac Surgery Department of Tor Vergata University, in Rome. Physical examination revealed short stature, depressed nasal bridge, hypertelorism, hypoacusia, pectus excavatum, diffuse brachydactyly, clinodactyly of the second digit of both the right hand and left foot. A 3/6 holosystolic increasing-decreasing murmur on the pulmonary focus was present at cardiac auscultation. Echocardiogram and cardiac catheterization revealed an ostium secundum atrial septal defect. X-ray examination of the hands exhibited shortening of the third, fourth and fifth metacarpals, shortening of the distal phalanges, shortening of the proximal and middle phalanges of the fifth digits and cone epiphysis of the middle phalanx of the second digits. Radiograph of the feet revealed shortening of the third and fourth and metatarsals on the left side, bilateral shortening of the first metatarsals and of the distal phalanges, cone epiphyses at the proximal base of the first toes. Additional radiographic findings included pectus excavatum and narrowing of the spinal canal. Laboratory investigations disclosed increased plasma levels of parathormone and hypocalcemia. The patient underwent primary closure of the atrial septal defect on cardiopulmonary bypass. Radiographic findings supported the diagnosis of Albright's hereditary osteodystrophy. This is a skeletal malformation involving type I-A pseudohypoparathyroidism and so-called pseudo-pseudohypoparathyroidism. Coexistence of hypocalcemia and high levels of parathormone indicated that our patient was affected with type I-A. About one-fourth of congenital heart diseases are associated with extracardiac anomalies. Although skeletal malformations appear to be the most frequent, the association of a congenital heart defect with Albright's hereditary osteodystrophy has never been described before.

Levels of troponin I and cardiac enzymes after reinfusion of shed blood in coronary operations.

BACKGROUND: Reinfusion of shed blood after coronary artery bypass grafting might increase the levels of cardiac enzymes with consequent difficulties in the diagnosis of perioperative myocardial infarction. METHODS: Thirty consecutive patients undergoing coronary artery bypass grafting who bled at least 400 mL within the first 4 hours after operation underwent reinfusion of shed blood. Thirty consecutive patients who were not autotransfused served as control. All patients underwent enzyme determination (total creatine kinase, MB fraction, lactate dehydrogenase, and troponin I) in the shed blood and in circulating blood preoperatively, at arrival in the intensive care unit, and 6, 24, and 48 hours after operation. RESULTS: The shed blood contained significantly higher concentration of cardiac enzymes than the circulating blood at all time intervals (p = 0.0001). The levels of creatine kinase, its MB fraction, and lactate dehydrogenase in circulating blood were significantly elevated in patients receiving autotransfusion up to 24 hours after autotransfusion. The blood levels of troponin I were not significantly different between the two group of patients at all time points. The percent fraction of MB did not increase after autotransfusion. CONCLUSIONS: The measurement of cardiac troponin I is a useful marker for the diagnosis of perioperative myocardial infarction in patients undergoing transfusion of shed blood after coronary operation.