ABSTRACT
Both aortic dissection and aortic aneurysm are complicated with disseminated intravascular coagulation (DIC) at the rate of four percent. DIC is said to be caused by the imbalance between coagulation and fibrinolysis and is classified into three types : suppressed fibrinolysis, balanced fibrinolysis, and enhanced fibrinolysis. Tranexamic acid has effects on suppressing the fibrinolytic system by inhibiting the mechanism by which plasmin decomposes fibrin. It is generally considered that the use of tranexamic acid for DIC is contraindicated. However, some reports show its effectiveness for non-infective chronic DIC. We illustrate two cases of DIC with enhanced fibrinolysis which are complicated with aortic dissection or aortic aneurysm that were successfully treated with tranexamic acid.
ABSTRACT
An 81-year-old man underwent aortic valve replacement with a 21-mm Medtronic Mosaic porcine bioprosthesis for the treatment of bicuspid aortic valve stenosis. In addition to the appearance of chest discomfort on effort and a new diastolic murmur, echocardiography performed 2 years and 3 months after the surgery showed a high pressure gradient across the bioprosthetic valve and a reduction in the valve orifice area. Prosthetic valve dysfunction was diagnosed. During a repeat operation, 2 large tears on the left cusp and a subvalvular overgrown abundant pannus were observed, and the bioprosthetic valve was replaced with a 19-mm On-X mechanical heart valve. On analysis of the explant bioprosthesis, the right non-coronary stent post was bent outwards by approximately 9°, it compressed the left cusp by pulling the left right and left non-coronary stent posts closer together, thus altering the leaflet geometry and function. We speculated that pannus formation had resulted from turbulent blood flow caused by impaired or altered leaflet function. The 2 large tears appeared to be the result of contact with the bias cloth secondary to the stent distortion.
ABSTRACT
A 36-year-old woman was admitted because of dyspnea on exertion and palpitations, during follow-up for ventricular septal defect since age 5. Physical examination revealed a grade IV/VI ejection systolic murmur at the second left intercostal space. Echocardiogram failed to recognize an unruptured aneurysm of the sinus of Valsalva protruding into the right ventricle which was seen on right ventriculogram (type I of Konno). Surgical treatment was successfully performed. Right ventriculography was much more effective rather than echocardiography in this case.
ABSTRACT
Ventricular Septal Defect (VSD) is the most frequent cardiovascular anomaly. VSD causes pulmonary hypertension through stenotic changes in the pulmonary vasculature, and this progress depends on the size of defect and associated cardiovascular anomalies. Since surgical repair has been performed in childhood for patients without a tendency toward spontaneous closure of VSD, operations in elderly patients, especially those aged over 40, are rare. We report an elderly patient with VSD complicated with severe pulmonary hypertension who underwent surgical repair. A 66-year-old man was admitted to our hospital because of general fatigue, chest oppression and palpitations. The pulmonary to systemic pressure ratio was 0.66. The oxygen saturation stepped up at the right ventricle level. The pulmonary to systemic blood flow ratio was 2.9, shunt ratio was 71% and resistance ratio was 0.12. The VSD was 18mm in diameter at the perimembranous trabecula and was closed with a Dacron patch through a right atrium incision. The lung biopsy specimen revealed little occlusive pulmonary vascular disease, Grade I according to the Heath-Edwards criteria. The patient had an uneventful recovery.
ABSTRACT
The effects of milrinone, a phosphodiesterase III inhibitor, were studied in patients with heart failure following coronary artery bypass grafting. Twenty patients with heart failure (either a cardiac index of less than 2.0<i>l</i>/min/m<sup>2</sup> or a pulmonary capillary wedge pressure of greater than 12mmHg) were divided into two groups according to whether or not they received postoperative milrinone administration. The control group (<i>n</i>=10) received no milrinone treatment and the milrinone group (<i>n</i>=10) received intravenous milrinone infusion at a speed of 0.5μg/kg/min postoperatively. The hemodynamic measurements were made perioperatively and clinical results were accessed perioperatively. Within-group comparison revealed a marked (<i>p</i><0.05) decrease in pulmonary capillary wedge pressure and systemic vascular resistance in the milrinone group. Cardiac indices were significantly (<i>p</i><0.05) greater in the milrinone group than those in the control group and within-group comparison revealed a significant (<i>p</i><0.05) increase in left ventricular stroke work index in the milrinone group. There was no significant difference in rate pressure product in between- and within-group comparison. The milrinone group had a significantly (<i>p</i><0.05) lower temperature difference between the rectum and the sole, and significantly (<i>p</i><0.05) less catecholamine requirements postoperatively. Milrinone was not associated with a significant increase in the prevalence of adverse effects. The results suggest that milrinone possesses positive inotropic and vasodilatory effects in patients with heart failure following coronary artery bypass grafting. In addition to catecholamines and vasodilators, milrinone may become a useful agent in the treatment of patients with postoperative heart failure.
ABSTRACT
The effects of human atrial natriuretic peptide (HANP, carperitide) were studied in 21 patients undergoing mitral valve surgery. The patients were randomized to receive either no carperitide treatment (control group, <i>n</i>=10) or carperitide (HANP group, <i>n</i>=11). Their hemodynamic status, diuresis and renal function were assessed perioperatively. The HANP group received continuous intravenous infusion of carperitide for 3 hours at a rate of 0.05μg/kg/min 3 hours after cardiopulmonary bypass. The HANP group had significantly lower systemic vascular resistance and less temperature difference between the rectum and the sole, and significantly greater cardiac index compared with those in the control group during infusion of carperitide, suggesting the improvement of cardiac performance by reducing afterload. The HANP group also had greater urinary output during the administration of carperitide, suggesting the significant diuretic effect of the regimen. The results indicated that the administration of carperitide may be a viable alternative strategy for the management of patients with postoperative heart failure. However, since transient oliguria was observed in 2 hypovolemic patients after the discontinuation of carperitide, careful monitoring is required during and after the infusion of the regimen in such patients.
ABSTRACT
Perioperative changes in thyroid function and hemodynamic state were studied in 6 hypothyroid patients and 15 euthyroid patients who underwent coronary artery bypass grafting. Serum free T<sub>3</sub> and total T<sub>3</sub> concentrations declined significantly in hypothyroid patients after the surgery. Serum total T<sub>3</sub> concentration decreased significantly also in euthyroid patients, indicating the occurrence of“euthyroid sick syndrome”in this group. Hypothyroid patients resulted in significantly lower left ventricular stroke work index despite greater central venous pressure and pulmonary capillary wedge pressure, and greater requirements of dopamine and dobutamine compared with those in euthyroid patients. The results indicated poorer postoperative cardiac performance in hypothyroid patients. Serum free T<sub>3</sub> concentration after cardiopulmonary bypass demonstrated a significant positive correlation with left ventricular stroke work index measured simultaneously. Preoperative serum free T<sub>3</sub> concentration showed a significant negative correlation with the postoperative dopamine and dobutamine requirements. Therefore, the results suggest that free T<sub>3</sub> has inotropic effects and the concentration of this hormone can be a predictor for a incidence of postoperative low cardiac output. In conclusion, since hypothyroid patients undergoing coronary artery bypass grafting are prone to have low cardiac output status, careful perioperative management, including hormone replacement therapy, is required for the patients.
ABSTRACT
A 44-year-old man presented with syncope and complete A-V block on electrocardiogram. Echocardiography revealed vegetation attached to the aortic, mitral and tricuspid valves. He underwent surgical repair because of uncontrollable congestive heart failure. The vegetation was attached to the noncoronary cusp entirely and had developed to the anterior mitral leaflet. The noncoronary sinus of Valsalva formed a giant mycotic aneurysm toward the right atrium and the aneurysm involved the tricuspid valve. The vegetation was resected together with the aortic valve and the aneurysm. Debridement was performed extensively on the right atrial wall and the aortic root. After closure of the orifice of the aneurysm with a bovine pericardium, aortic valve replacement was performed concomitantly with aortic annular reconstruction using a Hemashield<sup>®</sup> graft. Valvuloplasty was performed on the mitral and tricuspid valves. The technique described above enabled us to resect the infectious focus and successfully repair the defective tissues.