Relation of coronary artery stenosis and pressure gradient to exercise-induced ischemia before and after coronary angioplasty.

The purpose of this investigation was to evaluate the relation of coronary artery stenosis and associated pressure gradient to the magnitude of exercise-induced left ventricular dysfunction in patients with single vessel coronary artery disease. The percent stenosis and minimal cross-sectional area were measured before and after percutaneous transluminal coronary angioplasty and compared with radionuclide measurements of left ventricular function before and after angioplasty in 41 patients with proximal left anterior descending coronary artery lesions, providing 82 points of comparison. The gradient could be measured for 75 comparisons. Forty stenoses less than 50% were associated with a mean left ventricular exercise ejection fraction of 0.66 +/- 0.08 (mean +/- SD), 25 stenoses from 50 to 75% with a mean ejection fraction of 0.59 +/- 0.12 and 17 stenoses greater than 75% with a mean ejection fraction of 0.49 +/- 0.08. Thirty-five stenoses with a gradient less than 20 mm Hg were associated with a mean ejection fraction of 0.65 +/- 0.09, 24 with a gradient from 20 to 50 mm Hg with a mean ejection fraction of 0.58 +/- 0.13 and 16 with a gradient greater than 50 mm Hg with a mean ejection fraction of 0.53 +/- 0.10. These data document a relation between the magnitude of coronary artery stenosis and associated gradient to exercise-induced left ventricular dysfunction in homogeneous patient groups. However, discordance of these variables occurs commonly in individual patients.

Long-term experience in percutaneous transluminal dilatation of renal artery stenosis.

Percutaneous transluminal dilatation was attempted in 65 patients with renovascular hypertension. In five cases (8 percent), percutaneous transluminal dilatation could not be performed for technical reasons. In the remaining 60 patients (35 with atherosclerotic stenosis and 25 with fibromuscular dysplasia), both mean systolic and diastolic pressure fell immediately after percutaneous transluminal dilatation and remained significantly lower for a period of up to five years. Cure rates after a mean control period of 21.6 months were higher in patients with fibromuscular dysplasia (50 percent) than in those with atherosclerotic stenosis (29 percent). Improvement of blood pressure was observed in 32 percent of patients with fibromuscular dysplasia and in 48 percent of patients with atherosclerotic stenosis. Follow-up angiography in 33 cases showed occlusion of the dilated artery in two patients and recurrence of slight renal artery stenosis in nine patients. Successful redilatation could be performed in five of these cases. Furthermore, renal vein renin determinations were only of limited diagnostic or prognostic value. These results document the good long-term effect of percutaneous transluminal dilatation in patients with renal artery stenosis. Percutaneous transluminal dilatation should, therefore, be the favored procedure in patients with renovascular hypertension.

Percutaneous transluminal coronary angioplasty: report from the Registry of the National Heart, Lung, and Blood Institute.

Data have been collected from 34 centers in the United States and Europe performing percutaneous transluminal coronary angioplasty since September 1977. The procedure was carried out in 631 patients, with an average age of 51 years (range 23 to 76), of whom 80 percent had single vessel coronary disease, 17 percent had double or triple vessel disease and 3 percent had stenosis of the left main coronary artery. Coronary angioplasty was successful (greater than 20 percent decrease of coronary stenosis) in 59 percent of the stenosed arteries. The mean degree of stenosis was reduced from 83 to 31 percent. Emergency coronary bypass operation was required in 40 patients (6 percent). Myocardial infarction occurred in 29 patients (4 percent). In-hospital death occurred in six patients (1 percent), three with single vessel and three with multivessel disease. Ninety-one patients have been followed up for at least 1 year after coronary angioplasty. Of the 65 patients with an initially successful angioplasty, 83 percent were in improved condition compared with their status before angioplasty. Thus, the initial satisfactory results obtained in a few centers have now been confirmed in many centers using transluminal coronary angioplasty.

The role of the surgeon in percutaneous transluminal dilation of coronary stenosis.

Percutaneous transluminal dilation (PTD) of coronary artery stenosis is performed by means of a balloon-tipped catheter introduced from a peripheral artery. It was attempted in 45 patients; stenosis was passed in 33 and was successfully dilated in 28 patients (62%). The method failed in 17 patients: in 6 of them an abrupt closure of a stenosed artery or a beginning infarction necessitated an emergency revascularization. There were no deaths or serious complications, but an infarction developed in 1 patient despite immediate bypass grafting. PTD was successful in 5 out of 7 patients who had recurrent angina after previous coronary bypass grafting: in 2 of them stenosis of a distal coronary artery and in 3 a stenosed bypass graft were dilated. PTD is a new method of treatment of coronary artery disease and is an addition rather than an alternative to coronary bypass grafting. The best results can be expected in patients with single-vessel disease, with a short history of angina (less than 1 year), and with narrow, noncalcified proximal stenosis. Some late complications of bypass grafting are also amenable to this method of treatment.

Percutaneous transluminal coronary angioplasty: role of the surgeon.

Over a recent one-year period, 339 patients underwent percutaneous transluminal coronary angioplasty (PTCA) and were compared with 338 patients having isolated coronary artery bypass surgery. Patients undergoing PTCA had a shorter duration of angina, a lower number of prior myocardial infarctions, and better left ventricular function (p less than 0.01); PTCA was considered initially successful in 87% (295/339) of patients. Repeat angioplasty was performed in 18% of patients (34/339), with a successful outcome in all but 1. The most common finding at operation in those with failed angioplasty and urgent or emergency revascularization was dissection of an atheromatous plaque. There were 28 early failures (operation performed within 24 hours) and 24 late failures (operation at more than 24 hours), for early and late failure rates of 8.3% and 7.1%, respectively. Although the cumulative frequency of new Q-waves in the entire angioplasty series was low (2.7%), the incidence was high in those with angioplasty failure and subsequent operation (18%), and was significantly greater than in patients having elective coronary bypass (3.6%). Use of inotropic agents and lidocaine treatment for ventricular arrhythmias was also significantly higher in patients with unsuccessful PTCA who required operation than in those undergoing elective bypass (10% versus 3% and 10% versus 1.5%, respectively; p less than 0.01). Eleven of the 28 patients who were early failures were totally revascularized within 2 hours of angioplasty failure. Facilities and staff available for expedient revascularization accounted for the low morbidity and lack of mortality in PTCA failures.

Percutaneous transluminal coronary angioplasty: morphological findings in 3 patients.

Little morphologic information is available on the status of the major epicardial coronary arteries in patients dying after percutaneous transluminal coronary angioplasty. We studied hearts from 3 men (aged 60, 45 and 47 years) dying 3 days, 1 month and 7 months after balloon--dilatation of obstructed coronary artery segments. Twice the left anterior, once the left main coronary artery have been desobliterated. In one patient the procedure has not been successful and a venous bypass graft had to be implanted. Histologically the site of dilatation is clearly recognisable after 7 months. The characteristic findings are intimal tears in the segment opposite to the obstructing plaque. The intimal gaps are filled after 7 months by a neointima. In the dilated left main coronary we find 1 month after angioplasty an extensive proliferation of smooth muscle cells resulting in restenosis. Two patients died suddenly after an interval without angina. In the third patient--ome hours after bypass grafting--spasm of the non-involved right coronary artery occurred resulting in inferior infarction; this patient died 3 days after dilatation.

[Percutaneous recanalisation of chronic arterial occlusions (Dotter principle) with a new double lumen dilatation catheter (author's transl)]. / Die perkutane Rekanalisation chronischer arterieller Verschlüsse (Dotter-Prinzip) mit einem neuen doppellumigen Dilatationskatheter

A modification of Dotter's transluminal recanalisation of stenoses and occlusions of the superficial femoral artery, and of stenoses of the iliac artery, is described. In this procedure the occluding material is compressed not by successive catheters, but by a catheter with a dilatable cover. This catheter consisted originally of a single lumen, but now has double lumen; one lumen accomodates contrast, or a guide wire or a stiff cannula, whereas the second lumen is used for filling the cover and the expandable segment. The procedure is described in detail. Results so far appear satisfactory; they are compared with the results which have been obtained during the last year with the single lumen catheter.

[Cranial and caudal projections for coronary angiography (author's transl)]. / Kraniale und kaudale Projektionen bei der Koronarangiographie.

Cranial and caudal projections are a simple method for improving the diagnosis of coronary stenoses. In 20 cases out of 100 unselected coronary angiograms, the cranial projection showed stenoses to be more severe than had been demonstrated by the standard projection, or revealed them for the first time.

[Transluminal angioplasty of renal artery stenosis for the treatment of renal hypertension (author's transl)]. / Transluminale Angioplastie von Nierenarterienstenosen zur Behandlung des renalen Hochdrucks.

Three patients with hypertension due to renal artery stenoses were treated by percutaneous transluminal angioplasty with the coaxial-balloon-catheter system as it is used for the dilatation of coronary arteries. The pressure gradients before and after dilatation are recorded. Pressure of the three patients came directly after treatment down significantly. Reduction of antihypertensive drug therapy was possible in two patients, one patient is without therapy 4 weeks after the procedure.