Myocardial indium-111 antimyosin uptake after uncomplicated coronary artery bypass surgery.

The prevalence of myocardial damage after coronary artery bypass grafting is related to the criteria of its evaluation. Indium-111 monoclonal antimyosin antibody scintigraphy has been shown to be highly sensitive and specific for even small areas of myocardial necrosis or injury like those of myocarditis or transplant rejection. Our purpose was to evaluate, by using this method, myocardial damage after uncomplicated coronary artery bypass grafting. Uptake of this radio tracer was evaluated after coronary artery bypass grafting in 14 informed and consenting consecutive patients without previous myocardial infarction, with no post-surgical complications and a favorable postoperative course, following coronary artery bypass grafting for stable angina pectoris. Monoclonal antimyosin antibody indium-111 74 MBq (Myoscint Centocor) was injected on the third postoperative day; planar images in the anterior, left anterior oblique 45 degrees and 70 degrees projections were obtained 24 and 48 h later and analyzed for myocardial uptake. Indium-111 antimyosin uptake was present in 10 out of 14 patients (71.4%); it was diffuse in 6 and localized in 4. The ratio of the maximal counts in the myocardium to the counts in the adjacent lung background was measured and found elevated: 1.94 +/- 0.23, higher than the normal values reported in the literature. Indium-111 antimyosin uptake was clear in a group of patients after uncomplicated coronary artery bypass grafting. No correlation was observed between indium-111 antimyosin uptake or heart to lung ratio and creatine kinase, creatine kinase isoenzyme MB, glutamic oxalacetic transferase levels, duration of cardiopulmonary bypass or aortic cross-clamp time, while elevated serum beta myosin heavy chain fragments (IRMA Pasteur) were observed (1378 +/- 238 microU/l). This study suggests that some degree of myocardial damage, though silent, is common after coronary artery bypass grafting.

Perioperative myocardial cell damage assessed by immunoradiometric assay of beta-myosin heavy chain serum levels in patients undergoing coronary bypass surgery.

In order to investigate myocardial cell damage in patients undergoing coronary bypass surgery, serum levels of cardiac myosin fragments, using monoclonal antibodies to myosin beta heavy chains, were measured in serial blood samples of 85 patients, 79 male and 6 female, 43-66 years old, after a total of 86 internal mammary artery and 137 saphenous vein graft implants. Eight patients had perioperative acute myocardial infarction (MI), detected by abnormal Q waves and a rise of CK-MB levels. After surgery, beta-myosin levels increased from post-operative day 3 and reached peak values on day 5 in patients without and in day 7 in patients with perioperative MI, in these 8 patients, myosin peak levels were greater as compared to 77 patients without perioperative MI (3452 +/- 1596 vs. 761 +/- 494; P < 0.01). There was a correlation between myosin peak levels and creatine kinase (CK) (r = 0.71; P < 0.05) and CK-MB peak levels (r = 0.74; P < 0.05) only in the patients with perioperative MI, but not in the patients without MI. There was no correlation between myosin peak levels and the times of aortic cross clamping or cardiopulmonary bypass. Peak myosin levels over 75% confidence limits of the mean were found in 23 patients; post-operative low output syndrome occurred in 10 of these 23 patients and in 7 out of 62 patients with peak myosin levels within 75% of the mean (P < 0.005). The increase in beta-myosin heavy chain serum levels observed in almost all patients undergoing coronary surgery suggests lesser perioperative damage of the contractile apparatus, which could be detected by the usual enzyme and ECG criteria. The higher prevalence of low output syndrome in patients with higher increases in myosin levels suggests more pronounced damage to the contractile apparatus in these patients. The higher myosin levels clearly indicate the presence of perioperative MI.

[Myocardial protection during extracorporeal circulation. Preliminary results with different techniques]. / La protezione miocardica durante circolazione extracorporea. Risultati preliminari ottenuti con metodiche diverse.

Great advances in surgical techniques, perfusion technology and cardiac anesthesia have made heart surgery safer. However, the mayor advance over the past 15 years has been in the field of myocardial protection. Much remains to be done in this field and there is not complete agreement about the different methods of myocardial protection. At the Institute of Cardiac Surgery of Parma a research is developing to concern three different cardioprotective strategies, of which preliminary results are showing. Three groups of patients with the same clinical, surgical, anesthesiological features, who underwent cardiac surgery have been selected. In patients of group A intermittent cold hyperkalemic crystalloid cardioplegia has been used, in those of group B intermittent cold blood cardioplegia and in those of group C intermittent cold blood cardiolegia associated a warm glucose blood cardioplegic reperfusion before aortic unclamping. In all patients enzyme levels (CPK; CPK-MB; LHD; SGOT; SGPT) were measured 12, 24, 72, 120 hours postoperatively; data were collected, also, on spontaneous return to sinus rhythm, perioperative myocardial infarction and the need or not for inotropic agents. All data at first and then those of patients who underwent only coronary rivascularization (75% of patients) were statistically analyzed (one-way Fischer's test). It appears that the use of antegrade cold intermittent blood cardioplegia with reperfusion is more optimal for myocardial protection, how show lower levels of CPK-MB especially in the first postoperative period. In group C remains greater spontaneous resumption of normal sinus rhythm compare to group A and this suggests a best preservation of cellula-integrity and function with use of blood cardioplegia.

[Combined cardiac surgery and aneurysm of subrenal abdominal aorta]. / Chirurgia cardiaca e contemporanea resezione di aneurisma dell'aorta addominale sottorenale.

The authors explain their experience about the combined correction of cardiac pathology and infrarental aortic aneurysm repair. Seven patients of mean age of 63 years underwent simultaneous myocardial revascularization (5 cases) or aortic valve replacement (2 cases) and abdominal aortic aneurysm repair with bifurcated vascular prosthesis (6 cases) and tubular prosthesis (1 case) between 1987 and 1995. Cardiac operation was performed first with a mean number of 2.4 coronary artery by-pass grafts, with a mean by-pass time of 51 min, and a mean abdominal aortic cross-clamp time of 46 min. The mean total operating time was 231 min. All patients were managed postoperatively in the cardiac intensive care unit with a mean duration of 2.5 days and were transfused with a mean of 5 units of donor blood. The mean postoperative hospitalization was 9 days. One patient died for complication of postoperative myocardial infarction. The authors conclude that combined cardiac operation and abdominal aortic aneurysm repair is feasible in carefully selected patients.

[Our experience in the surgery of thoracic aorta]. / La nostra esperienza nella chirurgia dell'aorta toracica.

Particular interest was given to 61 cases of aneurysm and all possible risks and failures of the surgical procedures were discussed. The importance of how diagnostic, technical and instrumental investigations greatly improved therapy was emphasized. The largest group of patients investigated statistically was composed of patients suffering from acute aortic dissection. Emphasis was put on how modern diagnostic technology resulted in a faster and safe procedure, keeping in mind, however, that many severe cases were still unsuccessful. With regard to traumatic lesions of the aorta, typical of young patients, the importance of a complete clinical and surgical approach was stressed in order to treat the visceral and scheletral lesions that are often present.

[Radioisotope angiography in the differential diagnosis between aneurysm and pseudoaneurysm of left ventricle. Report of a case]. / L'angiografia radioisotopica nello studio discriminante tra aneurisma e pseudoaneurisma ventricolare sinistro. Descrizione di un caso.

We describe the case of a patient with large posteroinferior left ventricular aneurysm following myocardial infarction. Contrast ventriculography, Doppler echocardiography, as well as radionuclide angiography indicated a small orifice that was in communication with the ventricular cavity. These data suggested the presence of left ventricular pseudoaneurysm. Thus a short-term surgical intervention was performed, but the diagnosis was not confirmed by surgical observation; indeed the presence of a true aneurysm was demonstrated. Our study confirms the diagnostic difficulties by invasive and non invasive techniques in the precise identification of postinfarct pseudoaneurysm. This observation suggests the remarkable interest of our radionuclide ventriculographic results, not usually observed. Thus, we point out the possibilities of several nuclear cardiology imaging in the study of diagnostic problems concerning the analysis of these conditions of myocardial pathology.

Prevention of deep venous thrombosis by a new low molecular weight heparin (Fluxum) in cardiac surgery.

The prophylactic deep venous antithrombotic efficacy of a low molecular weight heparin (LMWH) was compared with traditional unfractionated calcium heparin in 39 patients submitted to cardiac surgery. The patients were allocated at random to receive either LMWH-Fluxum 3200 IUaXa daily (Group A: 20 patients) or calcium heparin 5000 IU three times daily (Group B: 19 patients). Both treatments were started on the first day after surgery and continued over the fourth postoperative days. One or more risk factors for deep venous thrombosis in addition to the cardiac pathology were present in all the patients of group A and in 13 (72.2%) of group B. Mean times of surgery, blood loss during the perioperative period and number of blood units transfused in both groups were not statistically significant. The deep venous system was investigated by continuous wave Doppler and real time colour Echotomography. No evidence of thrombosis was detected in the two groups. Side effects and subcutaneous hematomas were present in only four patients of group B. Both drugs showed good tolerance, provoking no variations of the main laboratory parameters. We conclude that Fluxum (LMWH) for the efficacy and convenience given by a single daily dose, could represent an alternative choice in the prevention of deep venous thrombosis in cardiac surgery.

[Assessment of perioperative myocardial damage based on circulating heavy chain myosin fragments]. / Valutazione del danno citomiocardico perioperatorio mediante dosaggio dei frammenti circolanti delle catene pesanti di miosina.

To evaluate myocardial damage induced by coronary bypass surgery, to construct a reference data set in postoperative patients and to ascertain the impact of perioperative myocardial infarction on myosin release from sarcolemmal membrane we serially measured levels of serum fragments of myosin heavy chains by means of monoclonal antibody immunoradiometric assay (MYOSIN IRMA ERIA Pasteur). After surgery serum levels of myosin increased from third postoperative day and peaked on seventh day. Peak myosin levels did correlate with enzymatic activities of CPK (r = 0.69; p < 0.001) and of CPK-MB (r = 0.75; p < 0.001). Six patients suffered postoperative myocardial infarction: in these patients myosin levels were significantly different from those without infarctions (3651 +/- 1569 versus 699 +/- 206 ng/ml; p < 0.01). No correlation could be demonstrated between cardiopulmonary bypass time or aortic cross clamp duration. The rise of myosin levels observed in nearly all patients suggests a minor intraoperative damage to the contractile apparatus that sometimes is diagnosed as myocardial infarction and often does not meet clinical diagnostic criteria.

Carotid endarterectomy under hypothermic extracorporeal circulation: a method of brain protection for special patients.

This study was undertaken to evaluate the efficacy of hypothermic extracorporeal circulation for cerebral protection in 17 patients having simultaneous carotid endarterectomy and cardiac operations. The cardiopulmonary by-pass (CPB) was conducted using total hemodilution. The body temperature was cooled to 25 degrees C and the heart was arrested with cardioplegic solution. The carotid endarterectomy was performed first followed by the cardiac operation. No neurological or cardiac complications occurred. These results support the reliability of hypothermic cardiopulmonary bypass as a method of providing cerebral protection during simultaneous cardiac and carotid surgical procedures.

[Intraoperative angioplasty and bypass for the treatment of diffuse symptomatic coronary lesions]. / Angioplastica intraoperatoria e by-pass per il trattamento di lesioni coronariche sintomatiche diffuse.

After a brief description of the intraoperative angioplasty technique carried out together with direct revascularization through bypass with venous segments or with internal mammary (IMA) we hereby report the immediate and mid-term results obtained in 18 patients with this treatment. The simplicity of execution, having the possibility to operate on still heart and under the direct vision of the lesion the rareness of any complication, the fact that the coronary segment is open also during all checks done after 3 years from the treatment, and finally the considerable improvement in clinical symptomatology, lead the authors to consider this therapeutical succession possible in some selected cases, for which surgical operation is necessary.

A comparative clinical study on the effects of cardiopulmonary bypass with different flows and pressures on skeletal muscle cell metabolism in patients undergoing coronary bypass grafting.

This study compares the effects of cardiopulmonary bypass with different flows and pressures on intracellular energy metabolism, acid-base equilibrium, and muscle water compartments in two groups of patients undergoing coronary artery bypass grafting. Eighteen patients (16 men and two women aged 54 +/- 7 years, New York Heart Association class I-II) undergoing low flow (flow rate 1.5 L/min/m2 at 26 degrees C), low pressure (mean arterial pressure 40 to 60 mm Hg) cardiopulmonary bypass, as well as 10 age-matched and sex-matched patients undergoing normal flow (flow rate 2.2 L/min/m2 at 26 degrees C), normal pressure (mean arterial pressure 60 to 80 mm Hg) bypass were studied. Intracellular acid-base equilibrium (intracellular pH and intracellular bicarbonate), cell energetics (adenosine triphosphate, diphosphate, and monophosphate, phosphocreatine, and lactate), and muscle water compartments were evaluated in specimens of the quadriceps femoris muscle obtained by needle biopsy before and at the end of cardiopulmonary bypass. In both the low flow-low pressure and normal flow-normal pressure groups, adenosine triphosphate levels were unchanged at the end of bypass, whereas phosphocreatine concentration was decreased; muscle total water and extracellular water increased without variations of intracellular water; muscle and plasma lactate increased as intracellular bicarbonate decreased; intracellular pH values remained unchanged. The present study suggests the following: (1) Cardiopulmonary bypass is associated with the overall preservation of intracellular compartment metabolism in skeletal muscle (about 40% of body cell mass) of patients undergoing coronary bypass grafting, even though low phosphocreatine values and increased plasma and muscle lactate values found at the end of bypass could be an expression of cell functional reserve exhaustion; (2) the effects of cardiopulmonary bypass on cell metabolism are comparable, regardless of the flows and pressures used.

[Is a simultaneous correction of coronary, carotid and major peripheral arterial lesions indicated?]. / E indicata la correzione contemporanea di lesioni coronariche, carotidee od arteriose periferiche maggiori?

The contemporaneous surgical treatment of coronary and vascular disease is still controversial. In the attempt to bring our contribution at this chapter, we present a case series of 69 patients, among 2149 operated on myocardial revascularization between January 1982 and December 1990, submitted simultaneously to aortocoronary bypass and vascular procedures, i.e. carotid endarterectomy or limbs' revascularization. The immediate and late results achieved through the combined surgical approach have shown a mortality slightly greater than the staged procedure. However, the absence of neurological or abdominal complication and the improvement in term of survival and life's quality encourage us to continue with this surgical strategy, whenever the clinical status of the patients and the pathological aspect of the lesions permit it.

Cell metabolism in patients undergoing major valvular heart surgery: relationship with intra and postoperative hemodynamics, oxygen transport, and oxygen utilization patterns.

The relationships between cell metabolism and both hemodynamics and oxygen transport/utilization (VO2/DO2) pattern were evaluated intra and postoperatively in eight patients undergoing major valvular heart surgery with the aid of moderately hypothermic cardiopulmonary bypass (CPB). Quadriceps femoris specimens were obtained by the needle biopsy technique for muscle ATP, ADP, AMP, phosphocreatine (PCr), creatine and lactate determination at anesthesia induction, after CPB, as well as in the ICU 18 h after surgery. Moreover, hemodynamic variables, oxygen transport and utilization indices, and plasma lactate were measured at the same intervals and throughout the CPB period. After CPB, muscle ATP and PCr contents were reduced (p less than .05) as compared to those of both pre-CPB patients and healthy control subjects; muscle and plasma lactate levels were increased (p less than .05). Mean VO2 and DO2 values measured during CPB significantly decreased (p less than .05), but VO2 reduction was proportionally greater than that of DO2 (-62% vs. -41%). No correlation was found between VO2 and DO2 at that time, but a significant relationship (p less than .05) was found at the end of CPB. A further decrease in muscle ATP and PCr levels was measured in the ICU, as muscle and plasma lactate levels were still elevated. At that time, VO2 and DO2 were not significantly different from pre-CPB values, but were significantly (p less than .05) correlated with each other.(ABSTRACT TRUNCATED AT 250 WORDS)

[Left ventricular function a short time after myocardial revascularization surgery: radioisotope angiographic study]. / La funzione ventricolare sinistra a breve termine dall'intervento di rivascolarizzazione miocardica: studio angiografico radioisotopico.

The short-term effects after coronary bypass surgery on left ventricular function were studied in 65 patients with coronary artery disease. Each patient underwent gated radionuclide left ventriculography on the second-third day before and 5-7 days after coronary bypass surgery. After surgery, global ventricular ejection fraction had a significant increase, anteroseptal wall motion was unchanged, while apical motion and mainly inferoposterior motion were significantly increased. The most important improvement of inferoposterior motion was observed in 18 patients who had complete revascularization of the previously infarcted inferior segments, while in the 11 patients with incomplete revascularization of the same area, inferoposterior motion had a slight increase. There was a slightly significant direct linear correlation between size and direction of the anteroseptal and inferoposterior motion changes. The patients were divided in subgroups related to the site and number of obstructed coronary vessels as well as of implanted grafts; the computed parameters showed similar changes in all subgroups. After surgery, peak ejection rate showed an evident increase, and time to peak reciprocally shortened. Peak filling rate, which had reduced preoperative values, was found clearly improved, with a corresponding shortening of the time to peak; these results confirmed that diastolic ventricular damage was a reversible disturbance related to myocardial ischemia. In 8 of the 65 patients, 24 hours urinary catecholamine levels showed similar values at both pre and postoperative radionuclide controls. In conclusion, the radionuclide angiography showed an evident improvement of left ventricular function during a short period following surgery, suggesting a better myocardial perfusion after revascularization.(ABSTRACT TRUNCATED AT 250 WORDS)

[Analysis using scintigraphy with thallium-201 of the perfusion picture before and after myocardial revascularization]. / Analisi mediante scintigrafia con tallio-201 del quadro perfusionale prima e dopo rivascolarizzazione miocardica.

The present study was undertaken to investigate the effects of coronary artery bypass surgery on myocardial perfusion analyzed by thallium-201 scintigraphy. In 34 patients early thallium-201 imaging, repeated 4 hours later at rest, was performed 2-3 days before and within 1 year following myocardial revascularization. Before surgery, exercise ECGs were positive in 22/34 patients, with scintigraphic perfusion defects in 33/34 patients; thallium-201 imaging showed reversible in 77 and irreversible perfusion defects in 51 myocardial segments. After surgery, exercise ECGs were positive in 3/34 patients, while thallium-201 perfusion data improved in 27, were unchanged in 4 and worsened in 3 patients. After surgery, thallium-201 imaging showed a remarkable improvement, with decreased number of reversible (8 segments) and irreversible (32 segments) perfusion defects. Ten of the 22 patients with previous myocardial infarction had improved irreversible perfusion defects in myocardial segments that were infarcted. Qualitative thallium-201 scintigraphy showed that myocardial revascularization exerted a clear favorable influence on reversible perfusion defects and in part on irreversible perfusion defects, suggesting that persistent defects are compatible not only with scar tissue, but also may represent hypoperfusion of viable myocardium.

[Surgical therapy of post-infarct aneurysm of the left ventricle. Immediate and long-term results]. / Terapia chirurgica dell'aneurisma post-infartuale del ventricolo sinistro. Risultati immediati ed a distanza.

Between January 1982 and December 1986, 62 patients (59 male and 3 female) ranging in age from 37 to 69 years (mean 53) underwent resection of postinfarction left ventricular aneurysm. The indication for operation was angina in 23 cases (37%), congestive heart failure (CHF) in 7 (11.2%), angina and CHF in 29 (46.8%), rupture in 1; 2 patients were low symptomatic. Ventricular arrhythmias were present in 6 (9.7%) cases and previous systemic embolism in 4 (6.4%). Forty-seven (75.8%) patients had lesions of three coronary arteries with involvement of left main coronary artery in 4 cases; 10 (16.1%) had lesions of two vessels [left anterior descending (LAD) and/or right coronary artery]; 4 (6.4%) had only LAD artery involvement, and 1 had no significant coronary artery stenoses. Left ventricular ejection fraction (EF) was less than 0.30 in 22% of cases, between 0.30 and 0.40 in 25.4% and greater than 0.40 in 50%. The location of the aneurysm was anterolateral or apical (83.8%), posterior (14.5%) and lateral (1.6%). Left ventricular aneurysmectomy with myocardial revascularization was performed in 61 patients (bypass/patient = 2.7), with ventricular septoplasty in 20 and concomitant mitral valve replacement in 3 patients. LAD was grafted in 59.6% of anterior aneurysm. Operative mortality (30 days) was 4.8%, the late mortality, with a follow-up between 12 and 72 months (mean 38), was 6.7% and the actuarial 5 year survival rate was 85% (91% without operative mortality). In our experience, despite no evidence of any operative risk factors, no improvement was noted in radionuclide left ventricular ejection fraction in patients undergoing aneurysmectomy with ventricular septoplasty.(ABSTRACT TRUNCATED AT 250 WORDS)

Right atrial hemangioma.

A case of right atrial hemangioma as a rare tumor of the heart is reported. Because of its single, pedunculated mass, surgical excision of the tumor resulted in the complete treatment. Histologically, it was classified as arteriolar type. The importance of recent non-invasive techniques to diagnose these tumors during life is emphasized.

Cell metabolism response to cardiopulmonary bypass in patients undergoing aorto-coronary grafting.

The main parameters of muscle acid-base, water and energy metabolism were studied in ten patients undergoing low-flux (1.5 l/min/m2), low-pressure (40 to 60 mmHg) hypothermic (26 degrees C) cardiopulmonary bypass (CPB) for aortocoronary grafting; absolute gas exchange and haemodynamic data were also measured throughout the entire CPB period. At the end of CPB a substantial preservation of water and energy metabolic indexes was found; a condition of extracellular metabolic acidosis was apparently sustained by muscle cell anaerobic glycolysis enhancement with a consequent increase of both muscle and plasma lactate content. Subnormal cell phosphocreatine levels as well as reduced bicarbonate buffer stores and decreased intracellular pH, were detected. Direct limiting effects of hypothermia on tissue O2 delivery and muscle oxidative metabolism as well as vasoconstriction and arteriovenous shunting associated with CPB procedures are likely to be involved in the above mentioned alterations of cell metabolism.