Multiple coronary arteriosystemic fistulas

A 58 year old man presented with angina pectoris and no heart murmur. On selective coronary angiography, multiple coronary arteriosystemic fistulas involving all three major coronary arteries were found. This is the first such case reported. It is speculated that this vascular anomaly represents persistence of embryonic intertrabecular vessels that permit the coronary arteries to communicate with the left ventricular chamber through the Thebesian vessels.     

Mechanism of closure of the mitral prosthetic valve and the role of atrial systole. Phonocardiographic and cinefluorographic study

Phonocardiographic and Cinefluorographic methods were used to study the mechanism of closure of the Starr-Edwards mitral prosthetic valve (model 6320) in 41 patients with a normal QRS interval. Atrial fibrillation was present in 23 patients and normal sinus rhythm in 18. The following intervals were measured: QRS to mitral closing click (Q-Mc), QRS to onset of closure (Q-Oc) and QRS to completion of closure (Q-Cc) of the prosthetic valve. Ball travel time was measured as Q-Cc minus Q-Oc. Mean Q-Oc was shorter in the group with normal sinus rhythm. In 8 patients in this group, Q-Oc occurred before ventricular systole and, in 2, completion of closure occurred before the QRS interval. Early closure in the group with normal rhythm was related to a prolonged P-R interval. In this group, values for Q-Mc and Q-Cc intervals did not differ significantly. Q-Cc in the groups with atrial fibrillation and normal sinus rhythm were not significantly different. Ball travel time was significantly longer in the latter group. Long R-R intervals in the group with atrial fibrillation may be associated with partial and occasionally complete premature closure of the valve. Q-Mc was inversely related to the R-R interval in this group.This study indicates 3 mechanisms for closure of the mitral prosthetic valve. Atrial or ventricular contraction alone may close the valve. The contribution of each is dependent on the time interval separating the contraction of these chambers. Spontaneous partial or complete closure may occur before ventricular systole during a prolonged R-R interval.     

Clinical and hemodynamic aspects of single vessel coronary artery disease

Two-hundred consecutive patients with arteriosclerotic heart disease underwent complete clinical and hemodynamic evaluation. Fifty-two patients (26 per cent) had significant single vessel coronary artery disease and were compared to 148 patients with more extensive coronary artery disease and to a group of 14 normal patients. The single vessel disease group, when compared to the diffuse disease group, was characterized by a shorter duration of angina pectoris, lower frequency of a history of congestive heart failure or cardiomegaly, and a lower frequency of electrocardiographic (ECG) evidence of a transmural myocardial infarction. The combination of angina pectoris for three or more years with cardiomegaly was the only factor which completely separated the two coronary disease groups. Cardiomegaly, when present in single vessel involvement, was always due to left anterior descending (LAD) disease, together with an anterior infarction on ECG and left ventricular asynergy. The single vessel disease group included 32 patients with LAD disease, 17 with RCA, and 3 with circumflex artery involvement. Resting hemodynamics in these 52 patients (other than a higher left ventricular end-diastolic pressure and wall stress) were not significantly different from hemodynamics in a normal group. Patients with diffuse disease were characterized by many hemodynamic alterations and by left ventricular (LV) asynergy, when compared to the single vessel disease or normal groups. The diffuse disease group had a lower ejection fraction (EF) and an increased frequency of LV asynergy and coronary collateral circulation than did the LAD group. In the single vessel disease group LV asynergy did not correlate with the ECG. LV synergy, however, was not found in any patient in the LAD group with abnormal Q waves on ECG. The single vessel disease group included only five patients with increased end-diastolic volume (EDV) and all had LAD involvement, increased LV end-diastolic pressure, and decreased EF. The remaining 47 patients with normal LV-EDV revealed that the LAD group had abnormal pressure-volume relationships, indicating a decreased compliance of the left ventricle.     

Reappraisal of the functional significance of the coronary collateral circulation.

A review of data in 465 patients with complete obstruction of either the left anterior descending or right coronary artery was undertaken to evaluate the functional role of the collateral circulation. Complete obstruction of a dominant right coronary artery was observed in 288 patients, 83 percent with distal filling and visualization of the posterior descending artery by way of collateral vessels. Complete obstruction of the left anterior descending artery was noted in 177 patients, 71 percent with filling and visualization distal to the obstruction by way of collateral vessels. Among patients with obstruction of the left anterior descending artery, there was a significantly greater frequency of congestive heart failure and cardiomegaly in those without collateral vessels than in those with collateral vessels. The former also had a significantly greater frequency of both electrocardiographic evidence of an anterior wall myocardial infarction and angiographic findings of anterior wall asynergy. The frequency of inferior myocardial infarction and inferior wall asynergy was not influenced by the presence of collateral vessels. These observations indicate that the collateral circulation plays a significant protective role in the presence of obstruction of the left anterior descending artery, which is not apparent with obstruction of the right coronary artery.     

Comparative study of the postoperative flow in the saphenous vein and internal mammary artery bypass grafts.

Postoperative coronary bypass flow was evaluated in two groups of randomly selected patients with grafts to the left anterior descending artery (LAD). Saphenous vein bypass grafts were placed in 27 patients and internal mammary artery grafts in 25 patients. Postoperative flow studies were performed in both groups with roentgendensitometric methods based on the transit time of radiopaque media along the graft plus the mean graft diameter. There was no significant difference between the two groups of patients for age, duration of symptoms, or the frequency of hypertension, diabetes mellitus, prior myocardial infarction, or cardiomegaly. Intraoperative bypass flows were 75+/-27 and 77+/-24 ml. per minute for the saphenous vein group (SVG) and internal mammary artery group (IMAG), respectively. There was no significant difference in the heart rate or mean aortic pressure at the time of the roentgendensitometric flow study. The mean graft diameters were 3.0+/-0.5 and 1.9+/-0.3 mm. for the SVG and IMAG, respectively (p less than 0.001). The ratios of graft diameter to LAD diameter were 1.9+/-0.3 and 1.2+/-0.2 for the SVG and IMAG, respectively (p less than 0.001). The roentgendensitometric postoperative flows were 68+/-27 ml. per minute in the SVG and 46+/-16 ml. per minute in the IMAG (p less than 0.01). The present study indicates that flow in significantly higher in saphenous vein than in internal mammary artery bypasses and that the difference in flow may in part be explained on the basis of the graft diameter.     

Correlation of heart size with clinical and hemodynamic findings in patients with coronary artery disease.

The clinical, hemodynamic, and angiographic findings were correlated with the heart size in 207 patients with proved coronary artery disease. Cardiomegaly was noted in 34 patients and normal heart size in 173. In these two groups, the patients' age range, duration of disease, and history of myocardial infarction were similar. There was no statistical difference in incidence of shortness of breath, hypertension, left ventricular hypertrophy, or abnormal glucose tolerance. Patients with cardiomegaly had a significantly higher incidence of congestive heart failure (26 per cent) as compared to patients with normal heart size (2.9 per cent) (P less than 0.001). Patients with enlarged heart presented a high incidence of anterior wall or multiple myocardial infarction (73 per cent) (P less than 0.001). The cardiomegaly group had a high incidence of elevated end-diastolic volumes, elevated end-diastolic pressures, and diminished ejection fractions when compared to patients with normal heart size (P less than 0.01). Double and triple coronary artery disease was more frequent in patients with cardiomegaly and total coronary score was also higher in this group (P less than 0.005). Asynergy was present in 55 per cent of patients with normal heart size but in 82 per cent of those with enlarged hearts (P less than 0.01). The group of patients with cardiomegaly and documented congestive heart failure had ejection fractions less than 0.30. Cardiac catheterization is probably not advisable in these patients in the absence of associated significant mitral regurgitation, ventricular septal defect, or ventricular aneurysm.     

Left ventricular hemodynamics and contractile pattern after aortocoronary bypass surgery. Factors affecting reversibility of abnormal left ventricular function

Left ventricular hemodynamics and contractile patterns were evaluated in 104 patients before and after aortocoronary bypass surgery. Patients were selected on the basis of referral for surgery because of angina pectoris and the demonstration, postoperatively, of all grafts being patent. Group I consisted of 47 patients with single grafts (LAD 33 and RCA 14). Mean left ventricular end-diastolic pressure, volume, and ejection fraction revealed no change after surgery. Twenty-four patients had asynergy prior to surgery; of these 24, 16 patients had a normal contractile pattern after surgery. Group II consisted of 47 patients with double vein grafts. Postoperatively, there was a significant decrease in left ventricular end-diastolic pressure (p < 0.005) and increase in ejection fraction (p < 0.001). Asynergy in 29 patients preoperatively revealed synergy after surgery in 15 patients. Group III consisted of ten patients with triple vein grafts. Ejection fraction increased postoperatively (p < 0.01). All but two of the eight patients with asynergy preoperatively showed synergy after surgery. In the entire group of patients, 43 with synergy preoperatively, with but one exception, had synergy after surgery. Asynergesis in 41 instances preoperatively revealed postoperatively that 38 patients (93 per cent) had normal wall movement. In 29 instances of preoperative akinesia of one wall, only 8 patients (28 per cent) showed a return to normal wall movement. Unstable angina pectoris alone did not influence reversibility of abnormal contractile patterns. Unstable angina pectoris with absence of abnormal Q-waves in the ECG was noted in 23 patients with asynergy; all but one of these patients had a normal contractile pattern after surgery. Patients with infarction pattern on the ECG, when accompanied by asynergy, were unlikely to have a normal contractile pattern after surgery (4 out of 23 patients). Reversibility of left ventricular function after surgery is common, not related to number of grafts, but is related to type of wall abnormality noted prior to surgery as well as the ECG and clinical state of the patient.     

Postextrasystolic aortic pressure pulse response in coronary artery disease.

The response of the aortic systolic pressure after an extrasystole was evaluated in 100 consecutive patients with coronary artery disease. The patients were divided into four groups depending on the response of the first postextrasystolic beat. Group IA (45 patients), had lower systolic pressure, whereas group IB (40 patients), had a similar systolic pressure in the postextrasystolic beat, as compared to beats preceding the extrasystole. Group IIA (12 patients) and group IIB (3 patients), demonstrated an increased systolic pressure in the first postextrasystolic beat with subsequent beats in group IIB, also demonstrating pulsus alternans. Congestive heart failure and cardiomegaly were significantly more frequent in group II, as compared to group I patients. In group IIA and IIB, triple vessel disease was present in 83 and 100 per cent, respectively, as compared to 44 per cent in group I patients. Left ventricular end-diastolic pressure (mm. Hg) was 14 ± 6 and 12 ± 7 in group IA and IB respectively, as compared to 19 ± 9 (p < 0.025) in group IIA and 31 in group IIB. Comparing groups IA and IB with each other for cardiac output, stroke volume, end-diastolic volume and ejection fraction, revealed no significant difference. The cardiac output (L./min./M.²) was 2.2 ± 0.6 for group IIA, as compared (p < 0.01) to 2.8 ± 0.5 and 2.9 ± 0.5 in groups IA and IB. Stroke volume (ml./M.²) and ejection fraction were 30 ± 10 and 0.30 ± 0.08, respectively, for group IIA, which is signficantly less, as compared to group I patients. The end-diastolic volume (ml./M.²) in group IIA was 102 ± 28, which is significantly (p < 0.001) higher, as compared to group IA and IB. All patients in group IIB had an abnormal cardiac output, end-diastolic volume and ejection fraction. Thus, the differences in response between group I and group II patients to an extrasystole clearly define two distinct hemodynamic groups. The responses observed to an extrasystole are best explained by variable response of each group to postextrasystolic potentiation and aortic impedance.     

Coronary arteriovenous fistula complicating aortocoronary bypass surgery

A coronary artery fistula complicating aortocoronary bypass surgery is reported in a patient. A continuous murmur heard on follow-up visits was the important clinical clue. The diastolic murmur was localized by intracardiac phonocardiography to the area of the tricuspid valve. A small left-to-right shunt was demonstrated in the right ventricle. Angiographic studies demonstrated a saccular structure arising from the left anterior descending artery, just distal to the anastomotic site and communicating with the right ventricle through a maze of vessels.     

Recurrent angina after bypass surgery: evaluation by early and late arteriography

Arteriographic correlates of recurrent angina pectoris were obtained in 98 patients undergoing both early (< 2 weeks) and late (five to 70 months, average 2.6 yrs.) postoperative angiography after coronary bypass surgery. All patients were discharged with arteriographic evidence of patency of all grafts (171 saphenous vein and six internal mammary artery) and all were asymptomatic during their early (< 3 month) postoperative follow-up. During late follow-up, recurrent angina occurred in 38 patients. The group with recurrent angina had significantly higher frequencies of progressive coronary disease (47% vs. 18%), incomplete surgical revascularization (35% vs. 15%), and graft closure (21% vs. 5%) compared to the asymptomatic group. In the total study group, 29 (30%) had progressive coronary disease with 16 (55%) having recurrent symptoms. Progressive coronary disease was present in 24% of ungrafted vessels compared to only 3% in native coronary arteries distal to graft anastomoses. The frequency of progressive coronary disease was directly related (p < 0.025) to the time interval between early and late arteriographic studies. The average annual rate of progressive disease was 10.7% of patients per year. Patients with progressive coronary disease had a higher (p < 0.05) cholesterol (264 ± 57 vs. 239 ± 37 mgm./dl.). Incomplete surgical revascularization was more common (61%) in patients operated on during the early (< 1.5 yrs.) experience with bypass surgery. Late graft closure occurred in 7.6% of all grafts and in 11% of patients. The average annual rate (attrition rate) of graft closure was 3% per year. Late graft stenosis occurred in 5% of patients but was related to angina pectoris in only one patient.The present study indicates that late recurrent symptoms may be anticipated after bypass surgery, since for the most part, they are due to progressive atherosclerotic process in the native circulation. Primary graft failure plays only a minor role in producing recurrent symptoms. Thus, continued control of risk factors, especially lipid abnormalities, is warranted after bypass surgery.     

Results of aortocoronary bypass grafting in patients with subendocardial infarction: late follow-up.

Twenty-eight patients with subendocardial infarction (Group A) were compared with 28 patients with unstable angina (Group B) and 28 with stable angina (Group C) matched for age and sex. The three groups did not differ in prevalence of diabetes, hypertension, old infarction or duration of disease. There were no significant differences in number of diseased vessels, coronary score, abnormal left ventricular wall motion or left ventricular end-diastolic pressure. Angiograms performed 2 weeks postoperatively revealed closure of 3 of 31 grafts (16 patients) in Group A, closure of 3 of 34 grafts (17 patients) in Group B and closure of 6 of 50 grafts (22 patients) in Group C (differences not significant). Postoperative angiograms showed improved wall motion in 37 percent of Group A, 53 percent of Group B and 36 percent of Group C (differences not significant). Postoperative new Q waves appeared in one hospital in Group A and in two patients in Groups B and C. There were no hospital or late deaths. In a mean follow-up period of 29 months, 68 percent of patients in Group A, 61 percent in Group B and 54 percent in Group C were asymptomatic. Thus, bypass grafting was performed with similarly low mortality and morbidity in patients with subendocardial infarction and in those with angina; more than one third of postoperative angiograms in the three groups showed improved wall motion; and late follow-up studies demonstrated functional improvement in the majority of patients in all three groups.     

Percutaneous transluminal coronary angioplasty: Its potential impact on surgery for coronary artery disease

The potential impact of percutaneous transluminal coronary angioplasty on surgery for angina pectoris was evaluated in 500 consecutive patients referred because of intractable symptoms. A positive lesion, that is, one appropriate for percutaneous transluminal coronary angioplasty, was defined as proximal, discrete, segmental, subtotal, noncalcific and stenotic. Significant disease was observed in 1,079 major coronary arteries, of which 9.4 percent were not appropriate for bypass surgery. Positive lesions were observed in 115 arteries (10.7 percent); these were in the left anterior descending artery in 60; in the right coronary artery in 37 and in the left circumflex artery in 18 cases. Main left coronary artery disease was present in 31 patients with six lesions appropriate for coronary angioplasty. Of these six patients none had isolated left main coronary artery disease. Operable coronary lesions were noted in 474 patients of whom 105 (22 percent) had positive lesions appropriate for angioplasty. The age of patients with such lesions was not significantly different from that of the remaining patients. However, the duration of clinical heart disease was significantly (p <0.01) shorter in those with positive lesions, with the frequency of such lesions inversely related to duration of disease, and myocardial infarction was less frequent in those with angioplastic lesions (28.6 versus 43.5 percent, p <0.01). An ideal patient for percutaneous transluminal coronary angioplasty was defined as one with a positive lesion in all operable coronary arteries. Thus, 40 patients were considered ideal for this procedure and represented 8.4 percent of operable candidates. Thirty patients had single vessel disease (of the left anterior descending artery in 19, the right coronary artery in 8 and the circumflex artery in 3) and 10 had disease of two vessels. No patient with triple or left main coronary artery disease was ideally suited for percutaneous transluminal coronary angioplasty. The only factor that distinguished the patient ideally suited for angioplasty from the remaining patients was a shorter duration (2.0 versus 4.1 years) of clinical disease (p <0.01) and a lesser frequency (15 versus 43 percent) of myocardial infarction (p <0.01). Seven additional patients were noted as being less ideal for coronary angioplasty, but still potential candidates. It is concluded that percutaneous transluminal coronary angioplasty may play a role in only 8 to 10 percent of patients with angina pectoris.     

Significance of new Q waves after bypass grafting: correlations between graft patency, ventriculogram, and surgical venting technique.

New postoperative electrocardiographic Q waves have been described in eight of 40 per cent of patients undergoing bypass grafting for coronary artery disease. Various theories have been proposed to explain these new Q waves. Correlations of new Q waves to vein bypass occlusion, prolonged pump time or aortic cross-clamping time are controversial. Indeed, whether or not the appearance of new postoperative Q waves means real transmural myocardial infarction is not clear. We report herein our experience with postoperative Q waves in 56 patients with vein bypass grafts and the relationship of new Q waves to ventricular venting, graft patency, and the postoperative ventriculogram. Our observations indicate that: (1) Not all Q waves are due to occlusion of the saphenous bypass grafts (as noted by others). (2) A certain percentage of new Q waves may not reflect true transmural myocardial infarction, especially when all the vein grafts are patent and the postoperative ventriculograms show improvement. (3) Some new Q waves reflect true transmural infarction due to occlusion of grafts or of distal coronary arteries with deteriorated left ventriculograms. (4) The high incidence of new Q waves in patients with ventricular vents is probably due to direct myocardial trauma at the apex of the left ventricle.