Retrosternal subclavian-femoral artery bypass.

In three cases we have used a retrosternal and extraperitoneal approach to revascularize the lower extremities with a subclavian-femoral artery bypass. This technique is as easy technically as the conventional subcutaneous axillofemoral bypass and has the advantage of avoiding extrinsic compression, thus improving long-term patency.

Escape of the disc occluder from a Beall model 104 mitral prosthesis.

A case of the escape of the disc occluder from a Beall model 104 mitral valve implanted 12 years earlier is reported. Acute dysfunction of the prosthesis was diagnosed and prompt operation was carried out. The patient, who was admitted in cardiogenic shock and pulmonary edema, survived and had a smooth postoperative course. Unnecessary investigations, which result in a delay of surgery, should be avoided under these circumstances. Since escape of the disc is rare with this type of valve (only one case has previously reported) elective reoperation is not recommended, but attention should be paid to the appearance of premonitory symptoms which may precede this dramatic event. Various investigations failed to located the embolized disc. Since no evidence of arterial obstruction was present, the patient was not submitted to an exploratory operation.

Surgical constriction of the pulmonary artery. A new experimental technique.

The classical "banding" of the pulmonary arterial trunk (PAT) is often difficult to remove at the time of definite repair of the cardiac congenital malformation; often its removal alone requires the use of a cardiopulmonary bypass and an angioplasty of the PAT. These difficulties have led the authors to study experimentally, in 16 dogs, the value of a palliative stenosis of the PAT by lateral compression (LC) of the arterial wall. Three types of compressing materials have been used: Teflon band wrapped in pericardium (5 dogs), cuneiform pieces made of either Teflon (5 dogs), or stainless steel (6 dogs). The experiment has led to the following conclusions: 1. The LC of the PAT is able to create a pressure gradient which tends to decrease when the animal is growing. 2. Cuneiform pieces made of Teflon or stainless steel should be used to realize the LC. 3. After the LC has been removed the PAT recovers its normal shape, as attested by absence of a systolic pressure gradient across the PAT. This technique of LC seems to be an interesting alternative to creating a temporary palliative stenosis of the PAT.

[Value of intravenous nitroglycerin in hypertension after extracorporeal circulation]. / Intérêt de la trinitrine intraveineuse dans l'hypertension artérielle après circulation extracorporelle.

The authors compare the haemodynamic effects of intravenous nitroglycerin (IV TNT) in 14 patients developing hypertension (mean blood pressure greater than 90 mmHg) and in seven normotensive patients (70 less than mean blood pressure less than 90 mmHg) after cardiac surgery with extracorporeal circulation (ECC). TNT was administered at doses of 0.5, 1, 2 microgram.kg-1.min-1 then 2 microgram.kg-1.min-1 with the association of vascular filling in order to restore right and left arterial pressures to their initial values. Various haemodynamic parameters were measured or calculated. The results obtained: in the hypertensive patients, at the low dose (0.5 microgram.kg-1.min-1) a prevalent venodilatory action was noted: RAP: 7.64 +/- 2.76 p less than 0.05; LAP: 9.07 +/- 3.19 p less than 0.05; at the middle dose (1 microgram.mg-1.min-1) venodilation continued resulting in a fall in BP 95.28 +/- 26.11 p less than 0.01 and above all in Cl: 2.28 +/- 0.36 p less than 0.01; at the maximum dose used, the action of TNT affected both the venous and arteriolar sector causing a major fall in BP: 89.64 +/- 23.88 p less than 0.001, in Cl: 2.29 +/- 0.33 p less than 0.01 and above all RVSI: 19.94 +/- 6.24 p less than 0.05. The association of vascular filling led to an increase in RAP and LAP (p = NS), Cl (p = NS) whilst BP remained low: 92.78 +/- 17.56 p less than 0.001 and also RVSI: 18.12 +/- 4.44 p less than 0.01. In the normotensive patients the administration of TNT, whatever the dose used, did not cause any significant changes (p = NS). In conclusion, the authors emphasise the value of the use of TNT in postoperative hypertensive states, in particular when associated with myocardial ischaemia.

Palliative reconstruction of the right ventricular outflow tract in tricuspid atresia: a report of 5 patients.

Five patients with tricuspid atresia, normally related great arteries, and decreased pulmonary flow underwent reconstruction of the right ventricular outflow tract on enlargement of the ventricular septal defect (VSD) (outlet foramen) or both in order to increase pulmonary blood flow. The age of the patients ranged from 9 months to 4 years. All patients previously had had a systemic-pulmonary artery anastomosis. Preoperative mean arterial oxygen saturation was 67.2%. A restrictive outlet foramen was enlarged in 3 patients. Infundibulectomy and enlargement of the outlet chamber with a Dacron patch were performed in 4 patients. A pulmonary valve commissurotomy alone was done in 1 patient. There were no hospital or late deaths (mean follow-up, 16 months). Four patients out of 5 have obtained symptomatic and documented (increase in partial pressure of oxygen) benefit. In 1 patient, arterial oxygen saturation failed to rise to a satisfactory level.

[Effect of intravenous nytroglicerin in hypertensive patients during and after open heart surgery (author's transl)]. / Impiego della trinitrina intravenosa nel trattamento dell'ipertensione peri-operatoria nel paziente operato in circolazione extra-corporea.

The present study was performed to compare hemodynamic effect of intravenous Nitroglycerin (TNT i.v.) in 14 patients developing acute hypertension (Group I) and in 7 non hypertensives after open heart surgery (Group II). In all patients, m.a. 56.6 yrs, (10 mitral and/or aortic prosthetic valve replacements, 9 aorto-coronary bypass, 1 open mitral commissurotomy, 1 closure of atrial septal defect) TNT was infused at doses of 0.5, 1, 2 microgram X kg X min. and subsequently at 2 microgram X kg X min. after volume administration (2 + V.A.) to maintain right and left atrial pressure the same as control (P = N.S.). Mean arterial, right and left atrial pressures (MAP, RAP, LAP), cardiac frequency and index (CF, CI and systemic vascular resistance index (SVRI) were monitorized. TNT i.v. resulted in hypertensive patients (Group I) in reduction vs. control of: a) RAP (--20.17%) and LAP (--20.58%) at 0.5 microgram X kg X min. b) RAP (--26.13%), LAP (--27.50%), MAP (--19.94%) and CI (--12.98%) at 1 microgram X kg X X min. c) RAP (--22.47%), LAP (--26.89%), MAP (--24.68%), CI (--12.6%) and SVRI (--17.34%) at 2 microgram X kg X min. When RAP and LAP was maintained by volume administration TNT i.v. (2 microgram X kg X min.) resulted in an even greater increase in CI and a greater decrease in MAP and SVRI ((--22.04% and --24.88% respectively). No significant hemodynamic modification (P less than or equal to 0.05) were observed in non hypertensive patients (Group II) at all doses of TNT i.v. The results confirm a predominant venodilator effect of TNT at low doses and a good effect on arterial resistances at high doses in hypertensive patients. In view of previous reports of differing effects on ischemia TNT i.v. may be preferable to other vasodilator drugs for control of acute post-ECG hypertension, only on condition to maintain an adequate left ventricular filling pressure to prevent a fall of cardiac index. Moreover the absence of significant (P less than or equal to 0.05) hemodynamic modifications in non hypertensive patients may be a further advantage in the treatment of myocardial ischemia with i.v. TNT.

[Left ventricular aneurysms. Hemodynamic studies and surgical results]. / Anévrysme du ventricule gauche. Etude hémodynamique et résultats opératoires.

The cardiac function of 37 cases of ventricular dyskinesia were studied by cineangiography. The amplitude and speed of contraction of the contracting parts was evaluated as well as the volume of the akinetic zone. A score of coronary artery obstruction was made for those patients who underwent coronary arteriography. All the patients had resection of their aneurysm. Four patients died in the immediate post-operative period. Six patients developed a temporary low output state requiring circulatory assistance. Twenty-seven patients were operated on successfully without posing any haemodynamic problem. Good immediate and late post-operative results were associated with an ejection fraction of the contracting part greated than 0,40, a dyskinetic area less than 40% and a coronary artery obstruction index of less than 6. Resection of the aneurysm, sometimes associated with aorto-coronary bypass grafting (5 cases), led to a marked improvement in heart failure and/or disappearance of ventricular arrhythmias.

[Variations in hemostasis in the infant under deep hypothermia]. / Variations de l'hémostase du nourrisson sous hypothermie profonde

Effects on hemostasis of deep hypothermia on infant has been studied on 29 infants operated upon for a cardiopathy under deep hypothermia. Results of this study show a diminution of the coagulation factors rate, an augmentation of the fibrinolytic activity and an unforeseable variability of the residual heparin leading in all cases to a complement of the heparin neutralization by Protamine.