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Collisional mountain belts grow as a consequence of continental plate convergence and eventually disappear under the combined effects of gravitational collapse and erosion. Using a decade of GPS data, we show that the western Alps are currently characterized by zero horizontal velocity boundary conditions, offering the opportunity to investigate orogen evolution at the time of cessation of plate convergence. We find no significant horizontal motion within the belt, but GPS and levelling measurements independently show a regional pattern of uplift reaching ~2.5 mm/yr in the northwestern Alps. Unless a low viscosity crustal root under the northwestern Alps locally enhances the vertical response to surface unloading, the summed effects of isostatic responses to erosion and glaciation explain at most 60% of the observed uplift rates. Rock-uplift rates corrected from transient glacial isostatic adjustment contributions likely exceed erosion rates in the northwestern Alps. In the absence of active convergence, the observed surface uplift must result from deep-seated processes.

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The author report the case of a 35 year old man who had undergone a Rastelli procedure in 1976 for transposition of the great arteries and who required indertion of a stent for stenosis of the valved right ventricular-pulmonary artery conduit. The patient presented with florid signs of right ventricular failure due to degenerescence of the conduit which had a 60 mmHg pressure gradient between the right ventricle and the pulmonary artery. This palliative procedure was decided upon given the high risk of reoperation. The valved conduit was dilated with a balloon catheter before insertion of a Gianturco stent (30 mm diameter and 50 mm long) to cover both conduit and the valvular apparatus. The insertion of the stent was easy with immediate normal expansion and the procedure was well tolerated. After insertion of the stent, the right ventricular-pulmonary artery pressure gradient fell from 60 to 35 mmHg. Angiographic control one month later showed a sustained hemodynamic result with a perfectly patent stent. The patient was pauci-symptomatic when reviewed six months after the procedure.

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Acute rejection is associated with severe impairment of coronary reserve in heart transplants. To evaluate the effects of rejection therapy, coronary reserve was assessed in 6 patients before and after treatment of an acute episode of rejection. Coronary reserve was significantly enhanced after rejection therapy (4.7 +/- 0.8, vs 2.3 +/- 0.5, P less than 0.001) and was not significantly different from that of transplanted patients without rejection (5.4 +/- 0.8). This study provides evidence that alterations of coronary reserve due to acute rejection are reversible after treatment of the rejection episode.

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Twenty nine patients (average age 11 years) underwent valvotomy for congenital valvular aortic stenosis from 1967 to 1983. The medium and long-term results were analysed retrospectively: 14 children have been reoperated; 11 for restenosis and 3 for aortic regurgitation after an average period of 11 years. Thirteen of the other 15 patients have been regularly followed-up for about 10 years: there are 7 good results, 3 average results and 3 restenoses. One patient was lost to follow-up after 9 years and the other patient died secondarily of a non-cardiac cause. This series was compared to a previous one of 35 cases of valvular aortic stenosis who underwent valvotomy between 1954 and 1964. There were 6 deaths in the perioperative period and 6 during follow-up (on average 11 years after surgery), including 3 sudden deaths. Eleven patients were reoperated: 2 for endocarditis, 5 for restenosis and 4 for aortic regurgitation (on average after 13 years). Three patients were lost to follow-up and there are 9 survivors who have not been reoperated (average follow-up 27 years): 5 of these patients were reexamined; there were 2 excellent results, 2 average results and 1 restenosis. These results show that conservative surgery of congenital valvular aortic stenosis is now a low risk procedure in children, but it is a palliative solution. The main problem is that of follow-up to detect restenosis because of the risk of sudden death. This follow-up is much easier since the introduction of Doppler echocardiography, eventually associated with exercise stress testing in doubtful cases.(ABSTRACT TRUNCATED AT 250 WORDS)

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During acute rejection, coronary vascular reserve is severely impaired in human orthotopic heart transplants. To evaluate the effects of rejection therapy on coronary vascular reserve, the ratio of peak-to-resting coronary flow velocity was assessed with a coronary Doppler catheter and a maximally vasodilating dose of intracoronary papaverine (12 mg) in nine allograft recipients without rejection (group 1) and in six recipients before and after treatment of an acute episode of rejection (group 2). All the patients had normal epicardial coronary arteries and were free of left ventricular hypertrophy. In group 2 during rejection, the coronary vascular reserve was significantly lower than in group 1, in which all the patients had a peak-to-resting coronary flow velocity ratio greater than 4 (2.3 +/- 0.5 vs. 5.4 +/- 0.8, respectively, p less than 0.001). In group 2 after treatment of rejection, the peak-to-resting coronary flow velocity ratio was similar to that of group 1 (4.7 +/- 0.8). Heart rate, left ventricular volumes and pressures, hemoglobin concentration, and arterial oxygen pressure were similar in the two groups. This study provides evidence that alterations of coronary vascular reserve because of acute rejection were reversible after treatment of the rejection episode.

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Two-dimensional echocardiography with intravenous injection of dipyridamole (0.56 mg/kg) was performed in 33 consecutive patients with acute (2 +/- 2 days) postero-inferior myocardial infarction for semiquantitative segmental wall motion analysis. The results were compared with those of coronary angiography which was carried out during the hospital period. After a second evaluation of the recordings the following results were obtained: feasibility: 94 per cent with 85 per cent of segments analysed. Residual ischaemia in the first days of myocardial necrosis was common (70%). The ischaemia was often clinically silent including during the investigation (61%). When pain occurred, it always followed changes in regional wall motion. The dipyridamole test suggested multivessel disease with a sensitivity of 72 per cent and a specificity of 90 per cent, and residual arterial stenosis with a sensitivity of 75 per cent ans specificity of 80 per cent the secondary effects were minor. The main limitation of the test is related to the distinction between pharmacological and physiologic ischaemia. A positive test was associated with lesions justifying myocardial revascularisation (coronary bypass or angioplasty) in 19 out of 23 cases but with a very poor correlation with the topography of the coronary lesions. A negative test indicated arterial occlusion, residual stenosis with extensive myocardial damage or a normal coronary angiogram. Therefore, the dipyridamole echocardiography test may help identify a group of patients with little or no myocardial ischaemia in whom invasive investigations could be deferred; these patients contrast with the group with a positive test indicating residual ischaemia in which the coronary lesions should be documented by coronary angiography.

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Thrombolytic treatment efficacy is greater when the delay between onset of pain and treatment is short. To give treatment before admission to a coronary care unit, responsibility needs to be transferred from cardiologists to other physicians working in mobile care units. We conducted a 2-part feasibility study to investigate this strategy. Part 1 evaluated the diagnostic accuracy of mobile care unit physicians. Results from this study indicate that with regard to the diagnosis of acute myocardial infarction, the risk of a wrong diagnosis is low. Part 2 was a placebo-controlled trial involving 100 patients in which 57 received anisoylated plasminogen streptokinase activator complex (APSAC) (30 U) at home and 43 received placebo at home. Patients receiving placebo at home were reevaluated on arrival in a coronary care unit and received APSAC (30 U) if indicated. The main results were that (1) diagnostic accuracy was good--all patients had an acute coronary syndrome and 97 of 100 patients had myocardial infarction; (2) time gain was approximately 60 minutes; (3) coronary patency rate was 72%; (4) ejection fraction was higher in the prehospital group (56.7%) than in the control group (53.4%), but the difference was not significant; (5) there was no rhythmic or bleeding complication related to the prehospital treatment; (6) 5 patients died from cardiogenic shock--2 between home and hospital and 3 in the hospital (3 received thrombolytic treatment at home and 2 received placebo at home and APSAC in the hospital); and (7) prehospital administration of APSAC did not induce a delay in arrival to the coronary care unit.(ABSTRACT TRUNCATED AT 250 WORDS)

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Enoximone (MDL 17043) is a new generation inotropic drug which acts by inhibiting phosphodiesterase and is endowed with both inotropic and vasodilator properties. The purpose of this study, which involved 23 patients aged from 18 to 75 years in NYHA class III or IV and with evidence of severe haemodynamic disturbances (cardiac index below 2.5 1/mn/m2, pulmonary wedge pressure above 15 mmHg), was to evaluate the acute haemodynamic responses to doses of enoximone that ranged from 0.25 to 2.50 mg/kg administered by bolus intravenous injection. Heart failure was either of ischaemic origin (6 cases) or idiopathic (10 cases) or due to various causes (7 cases). Group A patients (n = 11) received the drug in low doses (less than or equal to 1 mg/kg) as opposed to group B patients (n = 12) who were given high doses (greater than 1 mg/kg). Results were evaluated from the amplitude and duration of the haemodynamic response at maximum effect time (30 min). The following parameters were measured: cardiac index, pulmonary wedge pressure, systemic vascular resistance, mean arterial pressure and heart rate. Cardiac index and pulmonary wedge pressure were significantly improved in both groups (P less than 0.005): cardiac index +39 p. 100 in group A, +55 p. 100 in group B; pulmonary wedge pressure -36 p. 100 in group A, -48 p. 100 in group B; systemic vascular resistance -46 p. 100 in group B. Heart rate and arterial pressure were not significantly altered. The duration of response was 1 to 3 hours in group A patients and 4 to 8 hours in group B patients.(ABSTRACT TRUNCATED AT 250 WORDS)

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Six cases of cor triatriatum documented and operated on at Henri-Mondor hospital between 1980 and 1984 are reported. Ages at the time of surgery ranged from 8 months to 57 years. Four of the 6 patients presented with pulmonary hypertension. Anatomic types consisted of 4 diaphragmatic types and 2 more complex malformations. Associated lesions were present in all but one patients. They consisted mostly of interatrial defects (depending on their position with regard to the intra-atrial membrane, they play a determinant role in the symptomatology) and of a left superior vena cava (which might play a role in the embryogenesis of the malformation). Except for one early postoperative death, results of surgery were excellent for all patients, with a mean follow-up of 5 years. This series, compared with the literature, allows precising the embryologic and anatomic aspects of the malformation and the surgical techniques in complex types.

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Based on a study of 20 patients operated on between the ages of 21 and 38 for congenital valvular aortic stenosis, the distinguishing features of congenital aortic valvular stenosis in adults are reviewed: valvular calcification (75%), valvular dome rarely present (10%), usually moderate cardiac disability (70%), diminished or inaudible second heart sound (50%), associated diastolic murmur (75%), electrocardiographic left ventricular hypertrophy (70%), and an infrequent protosystolic click (30%). Surgery is necessary for symptomatic patients. If patients are asymptomatic, surgery is decided after measuring the left ventricle-aortic pressure gradient by continuous Doppler wave study, or by cardiac catheterization. If surgery is not performed, a regular follow-up is necessary because stenosis can evolve. Valvular replacement by a mechanical valve is preferable. Even if the aortic valve is not calcified and a simple commissurotomy is technically possible, it is only a palliative method with unsatisfactory results and an annual mortality rate after surgery of 1%.

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In a series of 833 operations with implantation of 1011 prosthetic valves there were 64 reoperations on 44 patients, an incidence of 7.6%. In almost 50% of the cases, reoperation was motivated by desinsertion. The incidence of desinsertions increased with the number of reoperations. In 40% of the cases, desinsertion was caused by endocarditis. The degeneration of bioprosthetic valves was rapid in children. Thromboembolic accidents occurred in patients with mitral valve mechanical prosthesis. Peri-operative mortality due to left ventricular dysfunction was 9%. Mortality rate was high after reoperation for endocarditis on a desinserted prosthetic valve. Surveillance and prevention of bacterial endocarditis remain of paramount importance.

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The records of 43 patients older than 18 years presenting with tetralogy of Fallot were retrospectively examined to determine the semiological characteristics of the disease in adults. One or more palliative operations had previously been performed in 27 patients. Full correction was carried out in 38 patients with results described below. Tetralogy of Fallot has the following characteristics in adults as compared with children: clinically, heart failure, attacks of angina, haemoptysis and sequelae of previous complications are more frequent; at electrocardiography, right atrial hypertrophy, right bundle disorders of conduction and ventricular extrasystoles are also more frequent; radiology shows that cardiomegaly is no longer exceptional; haemodynamic studies demonstrate an increase in right atrial and right ventricular end-diastolic pressures. These characteristics indicate a deterioration of haemodynamic adjustment to the disease with age. The operative morbidity mostly consisted of haemorrhages (55% of the patients), more frequent in subjects with permeable anastomoses (p less than 0.01), and heart failure (50% of the patients) the frequency of which increased with the subject's age, the duration of the operation and the use of an infundibulo-pulmonary prosthesis (p less than 0.05). The operative mortality (18%) depended on the extent of the pulmonary stenosis and on the presence of a previous anastomosis (p = 0.04). An analysis of the causes of death reported in the literature showed that in adults the presence of an anastomosis constitutes a separate risk factor in complete repair. The excellent long-term results of corrective surgery concerning cardiac function and survival suggest that except for those rare cases where the operative risk is very high all adults with tetralogy of Fallot should undergo complete repair.

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A 29-year old woman known to have Roger's disease was hospitalized for streptococcal endocarditis with pulmonary embolism and cerebral vascular accident. Echocardiography demonstrated vegetations on the pulmonary valve, and this was confirmed at surgery. Pulmonary valve endocarditis is a rare lesion sometimes occurring as a complication of congenital malformations with ventricular septal defect. Its prognosis is governed not so much by bacterial resistance or haemodynamic repercussions as by the risk of septic pulmonary embolism or systemic embolism. Prophylaxis is essential to avoid this dangerous complication.

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Previous clinical studies with intravenous enoximone have used cumulative dosing to quantify enoximone's hemodynamic effects. The magnitude and duration of the hemodynamic effects of single intravenous doses of enoximone were evaluated in patients with congestive heart failure. Sixty patients, who were in New York Heart Association functional classes III and IV, received single intravenous doses of enoximone, either 0.25 (12 patients), 0.5 (13 patients), 1 (14 patients), 1.5 (10 patients) or 2 mg/kg (11 patients). Cardiac index was increased by 20% with the 0.25 mg/kg dose and by 48% and 42% with the 1.5 and 2 mg/kg doses, respectively. These increases were statistically significant (Student's paired t test with Bonferroni's correction, p less than 0.007) for 1 hour after 0.25 and 0.5 mg/kg, for 2 hours after 1 mg/kg and for 4 hours after 1.5 and 2 mg/kg. Enoximone also reduced pulmonary artery diastolic pressure by 19% with 0.25 mg/kg and by 29% with 2 mg/kg. The duration of effect varied from 1 hour with 0.25 mg/kg to 4 hours with 2 mg/kg. Enoximone produced no consistent or dose-related effects on heart rate or blood pressure. Eighteen adverse reactions were reported by 15 patients, of which 11 were minor and transient (vein pain, flushes, nausea). In 5 patients ventricular or supraventricular arrhythmias were observed, including nonsustained ventricular tachycardia and extrasystoles; 3 of these patients had evidence of arrhythmias before enoximone. Laboratory studies before and after treatment showed no drug-related effects. Dose-related effects on the magnitude and duration of hemodynamic responses to intravenous enoximone were evident within the dose range of 0.25 to 2 mg/kg.(ABSTRACT TRUNCATED AT 250 WORDS)

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An angiographic study of 231 patients with tetralogy of Fallot (TOF) in both neonatal and adult age groups (0 to 49 years) was in this condition. Cases of pulmonary atresia with ventricular septal defect were excluded. Two types of collateral pulmonary circulation were observed: the most common form is the result of distal intrapulmonary anastomosis between systemic parietal, mammary and bronchial vessels with the pulmonary arteries. This type of collateral circulation represents an evolutive stage of TOF and is directly related to age and to the degree of hypoxia; the other, oa rare and probably congenital form (1.7 p. 100 of cases) observed even in young children, consisting of proximal anastomoses between systemic vessels arising from the aorta (1 to 3 vessels) and the pulmonary arterial tree. The rare forms of TOF with single pulmonary arteries acquired after palliative or congenital anastomoses (1.4 p. 100) have both types of collateral circulation. Preoperative diagnosis of the collateral pulmonary circulation requires opacification of the aorta especially of the descending thoracic segment and its branches, completed in cases of an absent pulmonary artery by wedged pulmonary venous opacification. The haemodynamic effects of this collateral circulation on the pulmonary bed to a variable degree of histological change. This may partially explain some of the poor surgical results of repair of TOF and, in view of recent progress in cardiopulmonary bypass techniques in children, incite to earlier surgical correction of this condition.

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