Haemodynamic effects of intravenous quinacainol with and without autonomic nervous system blockade.

Normal subjects are able to compensate negative inotropic drug effects by adrenergic stimulation. This may limit the relevance of hemodynamic investigations with new drugs. Therefore, the haemodynamic effects of a new class 1 antiarrhythmic drug, quinacainol, were evaluated in 16 patients with normal left ventricular function 5 and 25 minutes after intravenous administration in 2 settings: 12 patients were untreated, and 4 patients were pretreated with beta-blockers and atropine to block a reflex adrenergic discharge and vagolytic reaction. Cardiac contractility decreased in all patients: in the untreated group, the heart rate increased from 74 +/- 10 beats per minute to 80 +/- 9 and Vmax decreased from 1.56 +/- 0.56 circ/sec to 1.36 +/- 0.45 at 5 minutes and 1.36 +/- 0.61 at 25 minutes; in the pretreated group, the heart rate did not change. Vmax decreased from 1.61 +/- 0.19 circ/sec to 1.33 +/- 0.08 at 5 minutes and to 1.09 +/- 0.13 at 25 minutes. Autonomic nervous system blockade unmasked a significant persistent negative inotropic effect of the drug in this series of patients with normal left ventricular function. This method may be useful for evaluating the haemodynamic effects of antiarrhythmic drugs in preliminary studies before administration to patients with impaired left ventricular function.

[Mitral valvuloplasty during the 4th month of pregnancy. Fetal protection with a lead mantle]. / Valvuloplastie mitrale au quatrième mois de grossesse. Protection foetale par un manteau de plomb.

A 27 year old woman who had undergone closed heart surgical commissurotomy 10 years previously, underwent percutaneous mitral valvuloplasty during the fourth month of her pregnancy. Despite significant valvular thickening with calcification, the balloon dilatation led to an increase in valve surface area from 1.1 to 2 cm2 with no complications and with relief of the pulmonary hypertension. Foetal protection against ionising radiation was assured by a lead mantle completely surrounding the patient's abdomen. This protection reduced irradiation of the pelvic region to 0.5 milliSievert which corresponds to 1/100 of the permitted irradiation of pregnant women professionally exposed to ionising radiation.

Coronary blood flow reserve measured by contrast media injection depends on myocardial viability.

Coronary blood flow reserve may be affected by several physiological variables besides hydraulic impediment to flow. A hyperaemic response induced by hyperosmolar radiopaque contrast medium was recorded in the left anterior descending and left circumflex arteries with a steerable pulsed Doppler system in four patients with Q wave anterior myocardial infarction chronic scar and non-stenotic coronary arteries. Resting flow velocities were similar in both arteries. The magnitude of the hyperaemic response induced by contrast media in the circumflex artery (mean flow velocity increase from 5.9 +/- 2.5 baseline to 12.2 +/- 0.6 cm s-1 at peak flow, P less than 0.05) was almost twice that induced in the left anterior descending artery (mean flow velocity increase from 6.1 +/- 2.2 baseline to 7.4 +/- 2.6 cm s-1 at peak flow, P = N.S.). The peak flow to baseline flow velocities ratios were 1.22 +/- 0.15 in the left anterior descending artery vs 2.23 +/- 0.75 in the circumflex artery. Thus when a post-myocardial infarction chronic scar is supplied by a non-stenotic coronary artery, the coronary blood flow hyperaemic response to contrast media-induced transient ischaemia is decreased, suggesting that coronary blood flow reserve depends on a myocardial metabolic stimulus which is impaired by ischaemic cell death.

[Hemodynamic effects of quinacainol administered via an intravenous route. Study in patients with normal left ventricular function]. / Effets hémodynamiques du quinacaïnol administré par voie intraveineuse. Etude chez des patients ayant une fonction ventriculaire gauche normale.

The haemodynamic effects of a new antiarrhythmic drug quinacainol (RP 54272) were evaluated in 12 untreated patients with normal left ventricular function referred for diagnostic cardiac catheterisation. The haemodynamic data were obtained before, 5 and 25 minutes after the injection of the drug (0.21 mg/kg/min during 6 minutes). A slight decrease of cardiac contractility indexes was constantly observed: dp/dtmax decreased (-15%) in all patients (p less than 0.05), with no concomitant change of left ventricular pressure or left ventricular end diastolic volume with respect to control values. Cardiac output and left ventricular ejection fraction did not change significantly. Heart rate increased in all patients from 74.3 +/- 9.8 to 79.9 +/- 8.6 beats per minute after 5 minutes (paired t test p less than 0.05), and was 79.8 +/- 9.0 beats per minute after 25 minutes. Systemic arterial resistance increased in 7 patients due to a reflex adrenergic discharge. The interpretation of the haemodynamic data was difficult in 3 cases due to systemic vasodilatation, which was poorly tolerated in one patient. The contribution of vagolytic reaction and adrenergic reaction to the negative inotropic effects of the drug must be evaluated before giving in to patients with impaired left ventricular function.

[Evolution of the primary successes of percutaneous aortic valvuloplasty]. / Evolution des succès primaires de la valvuloplastie aortique percutanée.

Between November 1985 and August 1988, we performed 89 percutaneous aortic valvuloplasties. Sixty-two of these were considered a primary success on the basis of two main criteria: stage I or II on discharge and greater than 50 p. 100 increase in aortic valve area. The mean age of these patients was 78.4 +/- 6.1 years. On actuarial analysis, after 5 months 98 p. 100 of the patients with primary success were alive and 89 p. 100 were in stage I or II and had not been operated upon or redilated. At 15 months 79 p. 100 of the patients with primary success were alive, but only 48 p. 100 were in stage I or II and neither operated upon or redilated. Ultrasonic data obtained one and twelve months after dilatation were compared in 8 patients who had kept the full functional benefit of angioplasty for 14.6 +/- 4.3 months (group 1) and 9 patients who had lost this initial benefit (group 2). In group 1 patients the aortic valve area had moderately and non significantly diminished from 0.92 to 0.72 cm2. In group 2 patients the aortic valve area had gone down from 0.89 to 0.63 cm2 (p less than 0.01), indicating restenosis. We conclude that after the 4th post-valvuloplasty month the medium-term success of the procedure undergoes some degradation, and in these patients the echocardiographic signs of stenosis are clear-cut.

Results of percutaneous valvuloplasty for calcific aortic stenosis with different balloon catheters.

Percutaneous aortic valvuloplasty is a palliative treatment for patients with calcific aortic stenosis who would be poor candidates for surgical treatment. The results and associated complications of this procedure were analysed in a series of 47 patients in which different types of dilating catheters were used. In 25 patients a single balloon (19 mm) was used (group A), in 13 patients a bifoil balloon (2 x 15mm) (group B), and in the remaining nine patients (group C) a trefoil balloon (3 x 10mm) was used. An increase in aortic valve area was achieved in all patients. The results obtained with the bifoil balloon were better than with the other types of balloon catheter, with an increase in aortic area of + 118% vs. + 74% (monofoil) and + 76% (trefoil) (P less than 0.05). The tolerance of the inflation procedure was also better with this type of balloon, as it allowed for shorter inflation and deflation times. These results show that balloon aortic valvuloplasty, when indicated, is best performed with a bifoil balloon dilating catheter, and undue complications usually do not occur.

[Development of an ultrasonic system for the recanalization of coronary arteries]. / Elaboration d'un système à ultrasons pour désobstruction des artères coronaires.

We have devised an electro-acoustic system for the production and propagation of ultrasounds. With this system, linear vibrations can be transmitted through guides that are routinely used for coronary dilatation. Experiments performed on anatomical specimens have shown that ultrasounds are effective in destroying atheromatous formations. In addition, we tested this effectiveness with a setting that modelled the use of this system on the coronary vessels in terms of prerequisites: presence of a carrying catheter, aqueous environment, attention to vascular sinuosities and protection of arterial walls. The biological safety of low-frequency ultrasounds was tested in vitro and in animals. In view of these preliminary results, the subsequent development of an electro-acoustic system to be used in man seems to be justified.

Right heart failure due to an inter-atrial shunt after percutaneous mitral balloon dilatation.

Percutaneous mitral valve dilatation was performed in a 61-year-old female patient with severe mitral valve stenosis. The valve could be dilated, but a moderate left to right atrial shunt was present after the procedure. Although the mitral valve area had increased from 1 cm2 to 1.7 cm2, the patient presented 1 week later with right heart failure, explained by right heart volume overload resulting from the persistent shunt. Clinical status quickly improved with diuretics. Although this evolution has not been previously reported, it may be expected in older patients with decreased compliance of pulmonary arteries and right heart chambers.

[Course of aortic valve insufficiency in percutaneous aortic valvuloplasty]. / Evolution de l'insuffisance aortique lors de la valvuloplastie aortique percutanée.

The risk of occurrence or aggravation of aortic valve regurgitation after percutaneous aortic valvuloplasty was evaluated by angiography in 50 consecutive patients: 17 men, 33 women, mean age 77.6 years. In all cases angiography was performed with a pigtail catheter, trying to get the catheter in the same position for injections before and after dilatation. Forty-one patients showed no changes from the predilatation situation: aortic regurgitation was absent in 10 cases, minimal in 30 cases and moderate in 1 case. Minute leakage developed in a patient who had no aortic valve regurgitation prior to dilatation. Regurgitation decreased or subsided in 8 patients, i.e.: moderate leakage became minimal in 6 cases and minimal leakage completely disappeared in 2 cases. In the last 8 patients (3 men, 5 women, mean age 76 years) heart rate and transaortic diastolic pressure gradient were identical before and after dilatation, which means that the angiographic reduction of leakage was due to better closure of the valve. Aortic valve dilatation seems to carry a low risk of major aortic regurgitation. In patients who require percutaneous valvuloplasty for tight aortic valve stenosis, the presence of a small or moderate aortic leakage should not preclude the procedure from being performed.

[Reproducibility of myocardial ischemia induced by atrial stimulation]. / Etude de la reproductibilité de l'ischémie myocardique déclenchée par stimulation auriculaire.

Reproducibility of myocardial ischemia induced by atrial pacing (P) was investigated in 25 patients (pts) without previous anterior myocardial infarction and showing a positive exercise stress test. The second period of atrial pacing (P2) was exerted 20 minutes after the first (P1). During P2, a reduction in the parameters reflecting myocardial oxygen requirements (maximal left ventricular pressure, dp/dt max, TTI*HR values) was noted, while the signs of ischemia were less pronounced (ST depression decreasing from 2.3 +/- 1 mm to 1.6 +/- 1.0 mm; % of lactate extraction (%L) decreasing from - 6.4 +/- 25.5 to + 8.5 +/- 19.2; p less than 0.5). The 25 pts were divided into 2 groups according to the ejection fraction (EF greater than .55 16 pts Gr.F+; EF less than .55 9 pts Gr.F-). The distribution of coronary lesions was the same for the 2 groups. During P1 GR.F+ registered a negative % L as opposed to Gr.F-. During P2, the difference in the % L between the 2 groups was also significant (2.6 +/- 19.9% F+ vs 18.9 +/- 14.3% F-; p less than .05). Collateral circulation had no effect upon the results, neither for P1 or P2. This study shows that a second period of atrial pacing, 20 minutes after the first, induced lesser ischemia than the first period of atrial pacing. This phenomenon could explain the paradoxical improvement observed in certain patients after a first episode of angina. These results have implications as regards the necessity of double blind studies compared to placebo when using this technique in the evaluation of the effects of anti-ischemic drugs.

[Treatment by redilatation and thrombolysis of occlusion occurring during percutaneous coronary angioplasty]. / Traitement par redilatation et thrombolyse des occlusions survenant lors des angioplasties coronaires percutanées.

In patients who develop acute coronary occlusion during or after percutaneous coronary angioplasty, surgery is not mandatory, and other treatments may be considered, namely redilatation and/or thrombolysis. Between June, 1984 and January, 1988 we performed 500 dilatations of coronary arteries, not counting the attempts made in the acute phase of myocardial infarction. Acute coronary occlusion without angiographic image of occlusive dissection occurred in 31 patients (6.2%) and was treated by attempted redilatation and intracoronary thrombolysis. In 10 patients (group A) either the occlusion could not be removed and emergency surgery was tried (5 cases with 2 infarctions and 1 death), or the occlusion was removed but myocardial infarction took place (5 cases). In 21 patients (group B), the occlusion was removed and the outcome was favourable without myocardial infarction. Altogether, myocardial infarction or death occurred in only 8 cases, or 26% of acute occlusions. The clinical and angiographic features of the two groups before and after angioplasty were compared; two of them differentiated group A from group B: (1) unstable angina, 7/10 in group A, 4/21 in group B (p less than 0.01), and (2) degree of stenosis, 93.1% in group A, 78% in group B (p less than 0.01). When coronary occlusion occurs during or after coronary angioplasty and is poorly tolerated with fall in blood pressure, surgery must be contemplated at once, even after recanalization of the vessel and subsidence of ischaemia. In all other cases, treatment with both redilatation and thrombolysis should restore the benefits of angioplasty without myocardial infarction.

[Doppler study of phasic variations of blood flow velocity in the anterior interventricular artery]. / Etude Doppler des variations phasiques des vitesses du sang dans l'artère interventriculaire antérieure.

Studies of changes in coronary blood flow during cardiac cycles may be a useful adjuvant to the measurement of coronary flow reserve to evaluate the hydraulic severity of coronary arterial stenoses. We used intracoronary pulsed Doppler velocimetry to measure phasic variations of blood flow in the anterior interventricular artery of 12 patients with angiographically identified stenosis of that vessel. The Doppler signal was obtained by means of a 20 MHz emission from a source placed at the tip of a catheter selectively positioned at the ostium of the anterior interventricular artery, upstream of the stenosis. The increase in severity of stenosis was paralleled by a relative decrease of diastolic blood flow velocity in relation to systolic blood flow velocity. The diastolic/systolic maximum velocities ratio was greater than 1 in 6 patients with a less than 70 p. 100 stenosis (group A) and inferior to 1 in 6 other patients with a 70 p. 100 or more stenosis (group B). In 5 patients of group B this ratio was reversed to normal after percutaneous transluminal angiography. Thus, measurement of intracoronary blood flow velocity may be helpful to evaluate the severity of stenosis, notably in the anterior interventricular artery where angiographic evaluation is difficult.

[Results of percutaneous valvuloplasty in calcified aortic stenosis in the adult]. / Résultats de la valvuloplastie percutanée dans le rétrécissement aortique calcifié de l'adulte.

Aortic valvuloplasty by percutaneous valve dilatation was attempted in 52 patients aged from 60 to 88 years, 20 of whom were in functional stage IV with pulmonary oedema at the time of the procedure. Forty-seven stenoses could be dilated, with haemodynamic success (50 p. 100 increase of aortic valve area) in 44 patients. Among these 44 patients, 3 had to be operated upon because of persistent functional symptoms and 3 died during their stay in hospital (2 as a result of the procedure or the cardiopathy, 1 of heart failure unrelated to the aortic stenosis or the dilatation). The primary success rate therefore was 38/52 attempts, or 72.9 p. 100. The first 11 patients regarded as initial success could be followed up for at least 6 months: functional improvement with moderate myocardial alteration persisted in 9 of them, but Doppler examination in one showed restenosis. Two patients with severe myocardial dysfunction relapsed into cardiac failure; restenosis could be dilated in one of them. Percutaneous aortic valvuloplasty is an effective treatment of calcified aortic stenosis in elderly people who remain improved for at least 6 months when myocardial lesions are mild or moderate. The procedure incompletely reduces the aortic stenosis, which may account for the left of improvement in left ventricular function in patients with severe myocardial damage prior to dilatation. For this subgroup of patients, the choice lies between percutaneous valvuloplasty, which avoids surgery, and surgery which ensures a more complete haemodynamic result in the valve.