Cardiac Troponin I (cTnI) concentration in an ovine model of myocardial ischemia.

Cardiac Troponin I (cTnI) is a polypeptide involved in myocardial contraction and has been shown to be a highly sensitive biomarker of myocardial injury in humans. Chronic myocardial ischemia was induced in eight adult sheep by anterior coronary artery legation. Forty-five days after coronary artery legation, sheep underwent autologous myoblasts implantation to the infarct area to improve local tissue regeneration. Blood samples were taken at regular intervals before and after the induced coronary ischemia and myoblast implantation and serum levels of cTnI were assessed with chemiluminescent immunodosage using a commercially available anti-human cTnI monoclonal antibody. cTnI levels began to increase the day after coronary legation and after myoblast implantation and gradually recovered to physiological levels in the next 14 days. Furthermore, the commercial anti-human antibody was shown to completely cross react with the ovine polypeptide as well as with canine, swine and equine sera.

Endovascular treatment of a pulmonary artery pseudoaneurysm caused by Swan-Ganz catheter deployment in an anticoagulated patient.

We present a case report of an anticoagulated 78-year old man presenting a pulmonary artery pseudoaneurysm following Swan-Ganz catheter deployment after an aortic valve and aortic root replacement. Diagnosis was established by cone beam CT angiography and catheter angiographyand embolisation was achieved via a combination of plug and glue. This case emphasises the importance of endovascular techniques in the management of iatrogenic pulmonary pseudoaneurysms and shows the benefit of using highly hemostatic polymeric agent in anticoagulated patients to obtain a rapid and effective occlusion.

Coronary artery spasm in the rat induced by hypothalamic stimulation.

Anesthetized rats were sterotaxically implanted with electrodes and electrically stimulated in the lateral hypothalamus. During elevation of the S-T segment on simultaneous precordial electrocardiograms, the heart was perfused with glutaraldehyde-paraformaldehyde fixative and the major coronary arteries prepared for morphometry of luminal dimensions. A similar procedure was performed in a second group receiving intravenous arginine vasopressin (AVP) in place of hypothalamic stimulation. Elevation of the S-T segment was present in these animals as well. Control animals were implanted, not stimulated and otherwise treated in the same way. Morphometry showed that reductions of mean luminal diameter and cross-sectional area of statistical significance occurred in the two experimental groups compared to controls, suggesting that coronary spasm was the cause of the elevated S-T segments. Pooled plasma from separate groups of implanted control and hypothalamically-stimulated animals revealed substantial elevation of AVP levels in the latter raising the possibility that the neuroendocrine was involved in eliciting coronary artery spasm.

Hemodynamic, respiratory, and metabolic effects of medium-chain triglyceride-enriched lipid emulsions following valvular heart surgery.

STUDY: A lipid emulsion containing 10 percent medium-chain triglycerides (MCT) and 10 percent long-chain triglycerides (LCT) was infused at a rate of 1 ml/kg/h (3.3 mg/kg/min) for 2 h, in 12 patients (2 males, 10 females; mean age, 54 +/- 3 (SEM) years; range, 34 to 67 years) 24 h after open-heart surgery (mitral valve replacement). METHODS: Hemodynamic factors (pulmonary and radial artery indwelling catheters), oxygen and carbon dioxide partial pressures, oxygen saturation, oxygen delivery and consumption, and intrapulmonary shunt fraction were obtained before, during, and after lipid infusion (for 2 h), at 30-s intervals, along with some metabolic indexes (triglycerides, free fatty acids, glucose, insulin, lactate, acetoacetate). RESULTS: No statistically significant changes in heart rate, cardiac index, systemic and pulmonary pressures and resistances, central venous and pulmonary capillary pressures, or arterial oxygen partial pressure were observed during infusion. Arterial carbon dioxide partial pressure values were constantly reduced throughout and after the end of lipid infusion, as compared with baseline values, while oxygen consumption was increased significantly without any change in oxygen delivery. No adverse effects on intrapulmonary shunt fraction were observed. Statistically significant increases of triglycerides, free fatty acids, acetoacetate and insulin (peak values at end of the lipid infusion) were found in comparison with baseline values. Plasma glucose increased significantly during lipid infusion and remained higher than baseline values until the end of the study. Lactate levels were unchanged except for a slight decrease at the end of the study, without any derangement of acid-base equilibrium. Neither arrhythmias nor adverse clinical reactions were observed as a consequence of lipid infusion. CONCLUSIONS: Fat emulsions containing both MCT and LCT, when given at 3.3 mg/kg/min for 120 min following valvular heart surgery, do not exert negative cardiopulmonary effects, and could represent a source of rapidly metabolized substrates.

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.

Outbreak of acute renal failure due to cefodizime-vancomycin association in a heart surgery unit.

OBJECTIVE: To describe an outbreak of acute renal failure (ARF) occurring in a group of patients undergoing open-heart surgery, simultaneously to a change in perioperative antibiotic prophylaxis. DESIGN: Case series. SETTING: A nine-bed heart surgery intensive care unit, serving a 1,300-bed University teaching hospital. PATIENTS: Thirty-two patients undergoing open-heart surgery during an 11-day period, when the preoperative surgical prophylaxis protocol had been changed from the usual antibiotic association of ceftriaxone + vancomycin to cefodizime + vancomycin. RESULTS: ARF occurred in 16 of the 32 (50%) patients exposed to the new antibiotic prophylaxis regimen; seven patients had oliguric ARF, and nine patients had an increase in serum creatinine (SCr) levels >50% over 24-48 h. In the seven patients with oliguric ARF, SCr increased from a median preoperative level of 88 micromol/l (80-115 micromol/l) to a peak value of 725 micromol/l (521-857 micromol/l) in 5 days (4-6). Eight patients out of the sixteen with ARF (50%) were diabetics, as opposed to none of the 16 patients not experiencing ARF. Renal biopsy (three patients) showed tubular dilation and necrosis, interstitial edema, and lymphomononuclear infiltrate of moderate degree. Only one patient required hemodialysis, and all recovered renal function. No other cases of unexplained ARF occurred in the unit after the original prophylaxis protocol was resumed. CONCLUSION: The simultaneous infusion of cefodizime and vancomycin may involve a high risk of substantial renal function derangement, especially in diabetics.

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.

Asymptomatic patient reoperated on for severe proximal stenosis of circular sequential vein graft.

The case is described of a fifty year old man who underwent coronary bypass surgery using the circular sequential vein graft technique. At follow-up study (6 months after operation), despite his asymptomatic status, the effort test revealed antero-lateral myocardial ischemia. A coronary angiography showed a 90% proximal stenosis of the graft at 1.5 cm from the aortic anastomosis. The patient was reoperated on and the circular graft was reconstructed. Despite the severe stenosis this technique of myocardial revascularization has developed intercoronary anastomoses, improving the cardiac contractility and avoiding further clinical complications.

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.

Neurologic symptoms after great saphenous vein harvesting for coronary artery bypass grafting.

AIM: Incidence evaluation of cutaneous neurologic symptoms in the lower limbs as a new event after great saphenous vein (GSV) harvesting for coronary artery bypass grafting (CABG). Each day we harvest the GSV for CABG. Some authors have reported the onset of saphenous neuralgia complex as a new event of which we would evaluate the incidence. METHODS: From January 2000, until June 2001, 2,091 patients underwent cardiac surgery; 1,326 underwent CABG, 1,227 of them using the GSV as a conduit for almost one graft. These patients were prospectively reviewed; all were preoperatively examined to determine the presence of normal sensation in the lower limbs and elude the presence of saphenous neuralgia. Then, we evaluated sensations in the lower limbs at 5 days, 8 weeks, and 5 months after operation to determine the new onset of saphenous neuralgia. The areas of sensory loss were recorded each time and reported in a diagram to obtain 3 areas. RESULTS: Hyperaesthesia and pain were noted in a few patients, especially at 5 days and 8 weeks control, but at 5 months none of them complained of real pain. CONCLUSION: This study demonstrates that saphenous neuralgia after harvesting the GSV for CABG is a rare consequence. The main symptom is anaesthesia but its duration is generally no longer than 2 months. Hyperaesthesia and pain, for the early onset and the early disappearance, are considered as a normal consequence of surgical procedure.

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.

[Thallium-201 myocardial perfusion imaging after aortocoronary bypass in patients treated with sulodexide or ASA-dipyridamole]. / Analisi con tallio-201 del quadro perfusionale miocardico dopo bypass aortocoronarico in pazienti trattati con sulodexide ed in pazienti trattati con ASA-dipiridamolo.

The aim of this investigation was to compare the preventive effect of sulodexide, a glycosaminoglycan drug, tested versus ASA-dipyridamole association, on the occlusion of venous aortocoronary bypass. A group A of 23 patients, for a total of 22 anastomosis with internal mammary artery and 46 venous bypass, was treated with sulodexide 500 USL/day. A group B of 18 patients for a total of 19 anastomosis with internal mammary artery and 33 venous bypass, was treated with ASA-dipyridamole 300 mg + 400 mg/day. Three and 9 months after surgery, all patients underwent thallium-201 myocardial perfusion imaging, associated with ergometric test. At the first control after 3 months, reversible perfusion defect in one or more myocardial segments was observed in 8 patients of group A and 3 patients of group B (2 A patients and 1 B patient in non revascularized myocardial segments); after 9 months, reversible perfusion defects were observed in 4 A patients and in 4 B patients. After 3 months, non reversible perfusion defect imaging in non infarcted myocardial segments was observed in 2 A patients and in 1 B patient; after 9 months, in 1 patient of both groups. This research shows higher incidence, at first control after 3 months, of ischemic reversible perfusion defects in patients treated with sulodexide, with an evident improvement in some patients recontrolled after 9 months. At the last control after 9 months, the scintigraphic findings showed similar evidence of perfusion defects in both groups treated with sulodexide or ASA-dipyridamole, with concordant angiographic findings (78.6%). Our preliminary results are encouraging and suggest further widespread studies on sulodexide therapy.

[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)

Imaging of post-traumatic cardiac rhabdomyolysis with normal coronary arteries.

Numerous cases of acute myocardial infarction (AMI) have been reported in the literature following closed chest injuries, due to post-traumatic dissection or thrombosis of a coronary artery. In the follow-up of AMI, wall thickness during diastole and systole provides important information on heart viability. Multidetector computed tomography (MDCT) is currently the only noninvasive instrumental investigation which provides an appreciable assessment of the coronary arteries, as well as heart wall thickness measurements. We describe and discuss the clinical and imaging findings, especially of MDCT, in a case of post-traumatic regional myocardial necrosis with normal coronary arteries.

Primary cardiac Burkett's type lymphoma: transthoracic echocardiography, multidetector computed tomography and magnetic resonance findings.

Although primary cardiac lymphoma is an extremely rare disease and is associated with high mortality, it is treatable when diagnosed appropriately. We describe the transthoracic echocardiography, 16-row multidetector computed tomography (16-MDCT) and magnetic resonance findings of primary cardiac lymphoma in an immunocompromised patient and review of the literature.

MRI evaluation of myocardial viability.

Cardiac magnetic resonance imaging (MRI) has become an accurate noninvasive imaging procedure for the study of postischaemic residual cardiac function, thanks to the evolution of MRI machines, postprocessing software and, above all, sequences. After infarction, and in chronic myocardial ischaemia, the degree of contractile dysfunction is one of the main determinants of longterm survival. The identification and quantification of viable dysfunctional myocardium and the possibility of improving its contractility after revascularisation improves patient prognosis and quality of life. In current clinical practice, myocardial viability is evaluated with stress echocardiography and nuclear methods. Thanks to its intrinsic characteristics and to the delayed-enhancement technique (DE-MRI), MRI has recently emerged as the only noninvasive modality able to provide a three-dimensional (3D) evaluation of cardiac viability with a multiparametric approach.

Acute changes in circulating hormones in older patients with impaired ventricular function undergoing on-pump coronary artery bypass grafting.

OBJECTIVES: Coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB) causes an acute stress response characterized by changes in the levels of several hormones, which might play a role in the high complication rate experienced by older patients after CABG. Thus, the aim of the study was to investigate changes in the circulating levels of anabolic and catabolic hormones in old people undergoing CABG with CPB. DESIGN: Intervention case study. METHODS: 19 patients (12 males, 7 females) aged 70.1 +/- 6.1 yr (age range 62-80) with coronary artery disease and an ejection fraction <40% who underwent cardiac surgery. Cortisol (Cort), DHEA, DHEAS, LH, estradiol (E2), total testosterone (Te), SHBG, IGF-I were measured the day before, on the day of the procedure and 1, 2, 3, 4, and 30 days after CABG. RESULTS: After surgery, serum IGF-I levels decreased (p<0.001), while levels of Cort, DHEAS and E2 significantly increased in both men and women. Alterations in Te levels differed between the two sexes with a significant decline in men and a significant increment in women. CONCLUSION: CABG with CPB resulted in a dramatic drop in Te levels in old men and a significant decline in IGF-I in both sexes. Serum Cort levels also significantly increased in both sexes. These hormonal changes may, at least partially, explain why the elderly need prolonged rehabilitation after CABG.

Myocardial infarction in rats. Infarct size, myocyte hypertrophy, and capillary growth.

To determine the compensatory reserve capacity of the ventricular myocardium following infarction, the left coronary artery in rats was ligated, and the animals were killed 40 days later. Infarcts affecting an average 23% of the left ventricle were characterized by a 27% hypertrophic growth of the remaining myocardium that produced a complete replacement of the necrotic tissue. In contrast, infarcts with an average 50% loss of mass resulted in 83% expansion of the spared myocardium that was inadequate for a complete restoration of ventricular tissue. Myocyte hypertrophy was 26% and 78% in small and large infarcts, respectively. Cellular hypertrophy in both cases involved significant increases in myocyte transverse area and myocyte length. After large infarcts, there was an 18% reduction in capillary surface and a 16% increase in the diffusion distance. Corresponding values for small infarcts were -10% and 9%. These alterations combined with the deficient reconstitution of myocardial mass following large infarcts resulted in 25%, 29%, and 30% deficits in the absolute amounts of capillary lumen, surface, and length per ventricle respectively. Even with small infarcts, a deficit was seen in capillary luminal surface (-16%), and length (-19%). In conclusion, we have demonstrated that cardiac hypertrophy following myocardial infarction is consistent with cellular shape changes characteristic of a combination of concentric and eccentric hypertrophic growth. However, cardiac muscle cells appear to be unable to compensate for the loss of mass induced by a 50% infarct. The inadequate adaptation of the capillary vasculature in the infarcted hearts suggests that the injured ventricle is more vulnerable to additional ischemic episodes.