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The benefit of bilateral mammary artery (BIMA) use during coronary artery bypass grafting (CABG) continues to be debated. This study examined nationwide trends in BIMA use and factors influencing its utilization. Using the National Inpatient Sample, adults undergoing isolated multivessel CABG between 2005 and 2015 were identified and stratified based on the use of a single mammary artery or BIMA. Regression models were fit to identify patient and hospital level predictors of BIMA use and characterize the association of BIMA on outcomes including sternal infection, mortality, and resource utilization. An estimated 4.5% (n = 60,698) of patients underwent CABG with BIMA, with a steady increase from 3.8% to 5.0% over time (p0.001). Younger age, male gender, and elective admission, were significant predictors of BIMA use. Moreover, private insurance was associated with higher odds of BIMA use (adjusted odds ratio 1.24) compared with Medicare. BIMA use was not a predictor of postoperative sternal infection, in-hospital mortality, or hospitalization costs. Overall, BIMA use remains uncommon in the United States despite no significant differences in acute postoperative outcomes. Several patient, hospital, and socioeconomic factors appear to be associated with BIMA utilization.

Women historically have a greater risk of operative mortality than men after coronary artery bypass grafting (CABG). There is paucity of contemporary data in gender outcomes of surgical revascularization and understanding modifiable factors that contribute to gender differences are critical for quality improvement and practice change. We, therefore, sought to examine whether the gender gap in CABG outcomes is closing in the contemporary era by conducting a retrospective analysis from the Nationwide Inpatient Sample database from 2003 to 2012. We included all patients who underwent isolated CABG surgery (n = 2,272,998; female n = 623,423 [27.4%]; male n = 1,649,575 [72.6%]). The annual rate of CABG surgeries decreased by 53.7% in men and 57.8% in women over the 10-year study period. Although internal mammary artery use in women was less frequent than in men in 2003 (77.4% vs 81.9%, p0.001), a significant uptrend closed this gap by 2012 (86.2% vs 87.0%, ptrend 0.003). Overall, unadjusted in-hospital mortality was greater in women (3.2% vs 1.8%, p0.001). Female gender remained an independent predictor of mortality after multivariate adjustment (odds ratio 1.40, 95% CI 1.36 to 1.43, p0.001) across all age groups. However, in-hospital mortality decreased at a faster rate in women (3.8% to 2.7%, RR -29.1%, ptrend 0.002) than in men (2.2% to 1.6%, RR -25.7%, ptrend0.001) from 2003 to 2012. In conclusion, CABG rates in the United States are decreasing over time, yet in-hospital mortality continues to improve. Women have worse in-hospital outcomes than men; however, the gender gap is slowly closing.

Although in situ internal mammary artery (is-IMA) grafting remains the most frequent conduit in coronary artery bypass grafting (CABG), circumstances may necessitate free grafting of the IMA (f-IMA), though differences in outcomes have not been fully characterized. The purpose of this study was to compare clinical and angiographic outcomes of is-IMA versus f-IMA coronary bypass grafts in patients who underwent elective CABG surgery. In 1,829 patients in the angiographic cohort of PREVENT IV, 1,572 (85.9%) had at least 1 IMA graft; of these, 34 (2.2%) patients had at least 1 f-IMA graft and 1,538 (97.8%) had at least 1 is-IMA graft without additional f-IMA grafts. Characteristics of patients, procedure, and grafts/targets were compared between cohorts. Primary endpoints included death, myocardial infarction, and revascularization, as well as incidence of graft failure (stenosis >75%) on angiography at 12-18 months postoperatively. Patients receiving is-IMA grafts were more often of white race and higher weight. Aortic cross-clamp time was shorter in the f-IMA cohort (39.5 vs 57.0 min, p = 0.04), but duration of bypass was similar (93.5 vs 100.0 minutes, p = 0.793). Of the in situ grafts, 97.3% were via the left internal mammary artery (LIMA), 86.6% were of good quality, and the left anterior descending (LAD) was bypassed in 88.2%. This compares with free grafts, which were via the LIMA in 68.0%, of good quality in 96.1%, and bypassed the LAD in 58.8% and first obtuse marginal (OM1) in 23.5%. Rates of death, myocardial infarction, and revascularization were similar between groups. The rate of graft failure was higher in f-IMA grafts (23.3%) compared with is-IMA grafts (8.5%; p < 0.01). Although clinical outcomes were similar with use of free versus in situ IMA grafts, higher rates of graft failure were encountered with use of the f-IMA graft. In conclusion, in situ grafts should be the preferred conduit for patients who undergo CABG surgery.

In recent years, use of the internal mammary artery (IMA) as first graft of choice has been expanded with bilateral and sequential grafts in primary myocardial revascularization. The use of bilateral IMA grafts in reoperation has seldom been reported. The experience and early results with bilateral IMA grafting in 47 patients undergoing coronary reoperation are described. Hospital mortality was 6.3%. Four patients had postoperative signs of low cardiac output, and 4 had a perioperative myocardial infarction. At follow-up (18 ± 18 months), 2 cardiac-related, late deaths were noted. Thirteen patients (29%) improved 1 New York Heart Association class, and 28 (63%) improved >1 class. In 1 of 44 surviving patients, operation did not result in a decrease in angina. On the basis of the early results, the bilateral use of the IMA in coronary reoperation appears justified.

We present the case of a 65-year-old man who had undergone coronary artery bypass surgery 12 years previously. He presented with recurrent cardiac chest pain. Repeat coronary angiography showed anastomosis of the left internal mammary artery to the anterior cardiac vein. There was no evidence of a fistula formation. In conclusion, incorrect anastomosis of conduits is rare in cardiac surgery but should be considered, especially in the presence of symptoms or sign of fistula formation.

This study prospectively evaluated the diagnostic accuracy of 64-slice computed tomographic angiography (CTA) in assessing the patency of coronary artery bypass grafts compared with invasive coronary angiography. In total 147 bypass grafts (100 venous grafts and 47 mammary artery grafts) were evaluated in 50 consecutive patients. Contrast-enhanced 64-slice CTA was performed and compared with invasive angiography. The computed tomographic angiographic scan protocol used 64- x 0.5-mm slice collimation and 0.33-second gantry rotation time during simultaneous electrocardiographic gating. Patients with a heart rate65 beats/min received beta blockers. Overall 145 of 147 bypass grafts (98.6%) were detected by CTA; 2 nonvisualized grafts were occluded at the time of invasive angiography. Of the grafts visualized, 28 were totally occluded, 103 were patent, and 14 had significant stenoses that were confirmed by invasive angiography. Ninety-five percent (111 of 117) of patent grafts demonstrated good run-off distal to anastomoses but without an ability to accurately evaluate the presence of retrograde flow; 83% (97 of 117) of distal anastomoses were adequately evaluated, whereas the remaining 17% (20 of 117) were not well visualized due to vascular clips and/or calcification artifacts. Two grafts were not demonstrated by invasive angiography but were detected by CTA and found to be widely patent. In conclusion, multidetector 64-slice CTA is a valuable tool for direct visualization of coronary bypass grafts and assessment of their patency. Dysfunctional bypass grafts can be detected with high diagnostic accuracy.

Internal mammary artery (IMA) grafts are increasingly being used in the treatment of coronary artery disease. These conduits have been shown to have a low frequency of atherosclerotic narrowing, a high long-term patency rate, and a substantial beneficial effect on the survival of patients undergoing surgical myocardial revascularization. 1–4 Because the patency of the IMA graft is critical to long-term patient survival, stenosis of this graft postoperatively is a major clinical problem. The low graft attrition rate has limited our knowledge of the role of percutaneous transluminal coronary angioplasty in the treatment of IMA graft stenoses. Documentation of the safety and efficacy of IMA graft angioplasty has been limited to isolated case reports and series involving small numbers of patients with low angiographic follow-up rates. 5–11 This study describes our experience regarding the clinical and angiographic outcome after angioplasty of IMA graft stenoses in a consecutive series of patients with a high rate of angiographic follow-up.

Internal mammary artery angioplasty has been used as an alternative to repeat operation in patients with symptom recurrence after coronary bypass grafting. With use of standard balloon techniques, procedural success rates of 90 to 94% have been obtained, 1−4 but the limited number of patients with an unsuccessful angioplasty attempt has precluded analysis of factors affecting immediate procedural success and complication rates. Long-term follow-up of these patients has often been limited and difficult to interpret owing to infrequent repeat coronary arteriography and the presence of multivessel coronary artery disease. 1–6 To identify the factors affecting immediate procedural success and to characterize the long-term outcome of patients undergoing internal mammary angioplasty, we reviewed our experience with this procedure over an 18-month period.

We examined the relation of an ischemic syndrome with the progression of coronary disease early (

In conclusion, the well-preserved endothelial function of the IMA compared with that of the coronary artery might contribute to the higher patency rate among arterial grafts.

Internal mammary artery grafting in coronary artery bypass surgery has resulted in increased long-term patency and improved survival compared to venous bypass grafting. Angiography of the mammary arteries before bypass surgery is considered to be superfluous because they are rarely affected by atherosclerosis. 1 There are, however, no data on how often an internal mammary artery graft is intraoperatively rejected because of insufficient sluggish flow due to atherosclerosis. Early postoperative graft failure is said to be mainly related to technical errors. 2,3 To establish the frequency of atherosclerotic changes in the subclavian and internal mammary arteries among our patients, we performed semiselective angiography on both mammary arteries during cardiac catheterization in candidates for bypass surgery.

The GEA, though similar to the internal mammary artery in size and flow characteristics, is different histologically as well as physiologically. When used as a free graft, the GEA is very vasospastic, which may influence its long-term patency. When it is necessary to use the GEA as a conduit, it may be preferable to use it in situ rather than as a pedicle graft.

Four hundred consecutive patients, 80 percent of whom had multiple vessel obstruction, received a single internal mammary artery graft (121 patients) alone or combined with vein grafts (279 patients) in 1971 and 1972. Four patients died during or within 30 days of the operation. Sixteen patients had intraoperative infarction; three died. Arteriography was performed postoperatively (mean 12 months) in 254 patients, and 248 of 261 internal mammary artery grafts (95 percent) and 195 of 237 vein grafts (82 percent) were patient. Follow-up was complete (mean interval 38 months); all 80 patients with single vessel disease are alive, and the 3 year survival rate for patients with double and triple vessel disease was 98.7 and 94.4 percent, respectively. Comparison of longevity of 741 patients who had received vein grafts in 1967 to 1970 with that of 400 patients with internal mammary artery grafts (1971 to 1972) indicates greater survival for the recent series ( P

Two patients are described with continuous murmurs, maximum over the lower sternum, due to internal mammary artery fistulas. In 1 subject the continuous murmur was due to an internal mammary arteriovenous fistula; in the other, there was a communication between the internal mammary artery and the pulmonary arterial and venous branches to the left upper pulmonary lobe. Thorough diagnostic evaluation, including selective angiographic studies, is essential before removal of a thoracic wall arteriovenous fistula.

A plastic embedding technique was employed on mouse embryos after fixation with a gluteraldehyde-paraformaldehyde mixture and preparation of large, 1 to 2 μ sections cut on a rotary microtome with steel knives. It was then possible to trace the sinoatrial node back to mouse embryos of 4 sol1 2 mm crown-rump length ( 10 1 2 days gestational age, corresponding developmentally to 6 mm human embryos). In the mouse, the sinoatrial node lies anteromedially just above the cavoatrial junction. The nodal artery, which is located more or less centrally, is a branch of the internal mammary artery, not of the coronary arterial system. Even in the youngest embryos examined thus far, the node is strictly unilateral in structure.

Since December of 1956, 82 patients have been operated upon. The criteria for ligation of the internal mammary artery in the second interspace, was the presence of angina pectoris. No other factor except this was used in selecting these cases. Fifty of the cases have been followed for two to six months. When the report is made up of this group of fifty, it can be noted that eighteen are asymptomatic, eleven are moderately improved, five are slightly improved, eleven are unchanged. Three of the patients died within one month of surgery, two patients died more than a month after surgery. In dividing the cases up into basic pathologic patterns, it was noted that those with hypertension as well as coronary disease seemed to do quite well. The hemodynamic types which accompanied valvular disease were also benefited, although these groups were not large and made up only ten of the fifty. Of the five patients who were operated upon within two weeks of an acute infarction, three are now dead. One death occurred in a patient with lymphoma; another death occurred in a patient who had pyelonephritis and developed uremia. It is pointed out that local anesthesia seems to be safer than even light general anesthesia for this procedure. It is also evident that evaluation of this surgical procedure will have to be based on a formula involving large numbers of patients and much time, leavened by careful follow-up studies.

The medical aims of treatment are to relieve symptoms by psychotherapeutic, pharmacologic, and physical means. Diet is briefly mentioned in the light of recent discovery that fatty meals can produce anginal pain even though the meals are small in volume. In the discussion of care of bowel function, it is felt that the use of the bedpan has more hazards than advantages in these cases. Brief mention of the advantage and risk of oxygen therapy is made. There is no discussion in this paper of anticoagulants, digitalis, or quinidine; other papers presented at the same time cover these factors. A new operative procedure, bilateral internal mammary artery ligation in the second interspace, is discussed. There are many problems connected with this surgery which are still to be answered; however, the results thus far are promising.

Electrocardiographic changes occurred during angiographic injection of the internal mammary arteries in dogs with pericardial splenosis and previously ligated coronary arteries. These electrocardiographic changes appear to be the result of the radiopaque material reaching the myocardium directly from the internal mammary arteries through the pericardial splenosis, as demonstrated by the short interval of time between the start of the injection and the onset of the electrocardiographic changes. The dramatic electrocardiographic changes, with timing measurements correlated with the simultaneous angiograms, support the validity of such conclusions in 2 of 6 test animals. No such electrocardiographic changes occurred with angiographic injection in 3 control dogs and in 4 other test dogs similarly injected. The India ink injections indicate anatomic pathways from the internal mammary arteries through the pericardial splenosis into the coronary arterial system within the myocardium. The electrocardiographic changes indicate an unmeasured but apparently significant quantity of collateral flow. If such pathways can develop, the problem then appears to be one of producing profuse splenotic growth more regularly.

in its normal orientation. Now, everyone feels uncomfortable if the image is upside down. If the available ultrasound equipment does not have an “invert” switch, the recorded images may be photographed and the negative inverted to make prints with the heart right side up for publication. The 2-dimensional echocardiogram has become the most widely used noninvasive imaging technique for evaluation of the heart. Its value is diminished by clinging to the custom of showing the heart upside down when imaged by echocardiography, but rightside up when imaged by roentgenography, angiography or nuclear cardiology. I believe there are several steps toward the solution to this problem: (1) Medical journals could insist that 2-dimensional echocardiograms be oriented in the anatomical position. (2) The American Society of Echocardiography could make a stronger recommendation regarding image orientation. (3) The major scientific cardiology meetings could require standardization of image orientation to minimize audience confusion. (4) Physicians and technicians performing echocardiography should insist that the manufacturers of ultrasound equipment provide the means of visualizing the heart in its normal orientation when imaged from the apical or subcostal locations.

L IGATION of the internal mammary arteries for treatment of angina pectoris and coronary heart disease has been discussed in many publications. Reference to these publications is omitted from this paper. Only our experiments are reported. Various tests were established in our laboratory to measure the beneficial effect of a drug or a surgical operation upon the coronary artery circulation. These tests are as follows: (1) backflow measurements; (2) electrical fibrillation (mortality) after test artery occlusion; (3) size of infarct after test artery occlusion and (4) the electrical condition of the heart after test artery occlusion. Each of these tests is related to the amount of oxygenated (arterial) blood delivered to an area of ischemic muscle. When the amount of blood to an area of ischemic muscle is increased by therapy, the condition is improved ; when it is reduced, the opposite effect is produced. These statements apply to both the human subject and the experimental dog. The effect of ligation of the mammary arteries on these tests has been studied.

of the thoracic aorta has been used in some centers only in children lz2 because its viability may be questionable in adu1ts.l On studying these arteriograms in our institution, we noted that the internal mammary artery (IMA] was always contrasted by the peripheral injection. We decided to test the technique in adults

Thirty-two consecutive patients who earlier received indirect or direct myocardial revascularization underwent reoperation with one or more internal mammary artery grafts either alone or in combination with saphenous vein grafts. The main indication for reoperation was graft closure or progression of coronary atherosclerosis in nongrafted vessels, or both. Graft construction was performed under normothermic perfusion and anoxic arrest with interrupted suture technique. No intraoperative infarctions or hospital deaths occurred. All patients are alive after an average follow-up period of 20 months, and two thirds are asymptomatic. Arteriography after reoperation in nine patients revealed patency of eight of nine internal mammary artery and five of five secondary vein grafts. When angiographic and symptomatic indications for reoperation exist, the internal mammary artery bypass graft has become a valuable alternative, particularly for patients with small coronary vessels or previous vein graft failure.

Spontaneous spasm of native coronary arteries and saphenous vein bypass grafts has previously been demonstrated by coronary angiography. 1,2 Direct observation of spasm involving internal mammary artery (IMA) bypass graft has been reported in the immediate postoperative period. 3 We present angiographic documentation of spasm in left IMA bypass graft in the late postoperative period.

1. (1) We have presented 36 cases of severe coronary artery disease treated by surgical procedures—cardiopexy, internal mammary artery ligation, and Beck I operation. 2. (2) Clinical improvement was noted in 30 of the 36 cases (83 per cent). Excellent results (complete or almost complete disappearance of angina) occurred in half the patients. 3. (3) Objective evidence of improvement as measured by the electrocardiograms and ballis-tocardiograms in several cases is presented. 4. (4) The internist and cardiologist should recognize that improvement may be offered by surgical technics in the treatment of coronary artery disease.

A sham operation was compared to ligation of the internal mammary arteries in patients with angina pectoris. Patient improvement was identical. The exercise electrocardiogram was not altered by either procedure.

1. (1) Bilateral ligation of the internal mammary arteries was performed on a total group of 304 unselected patients with various degrees of coronary artery disease. These patients have been followed up from six months to four years after the surgical intervention. 2. (2) Symptomatic improvement occurred in 288 cases (94.8 per cent); no improvement was noted in 15 cases (4.9 per cent). During the follow-up period, the initial improvement was not maintained in 14 patients (4.6 per cent). No death occurred during or in the immediate postoperative period. Thirteen patients died at various intervals after the surgical procedure; 8 died of cardiac disease, and 5 patients of other causes. 3. (3) In 195 cases (64.1 per cent) the electrocardiogram improved after surgery, even though no strict relationship was found with the clinical improvement. 4. (4) Ligation of the internal mammary arteries is a simple surgical procedure which produces an increased blood supply to the myocardium through natural and pre-existing anastomotic channels. 5. (5) Our results compare favorably with those obtained by more complex and dangerous attempts at myocardial “revascularization.”

Spontaneous spasm occurring in native coronary arteries in the absence of fixed atherosclerotic disease carries a generally favorable prognosis 1 ; only occasionally does it result in myocardial infarction. Spasm of saphenous vein and left internal mammary artery grafts has been demonstrated in the immediate postoperative period, and can result in hemodynamic collapse. 2,3 In addition, although rare, spasm of both saphenous vein and left internal mammary artery grafts presenting with recurrent angina pectoris several years postoperatively has been angiographically documented. 4,5 To our knowledge, late postoperative spasm in a bypass conduit has never been linked to transmural myocardial infarction. We recently studied a patient who sustained a transmural anterior myocardial infarction related to spontaneous reversible spasm of a left internal mammary artery graft.

Since the advent of coronary artery bypass grafting in 1967, ventricular intramyocardial implantation of an internal mammary artery (IMA) directly into left ventricular (LV) myocardium (Vineberg procedure)l has been supplanted. We recently studied the heart of a patient who had undergone concomitant aortocoronary bypass grafting with a saphenous vein (SV) and implantation of an IMA into LV myocardium nearly 16 years earlier. This case provided an opportunity to examine 2 types of vessels used for myocardial revascularization.