Anastomosis Of Internal Mammary Artery Research Articles

Cardiac stabilizer for minimally invasive direct coronary artery bypass

We describe a simple and effective device that is useful in reducing cardiac motion, enabling the surgeon to perform a precise direct left internal mammary artery anastomosis to the left anterior descending coronary artery on a beating heart.

Local immobilization of the left anterior descending artery for minimally invasive coronary bypass grafting

We describe a device for coronary artery stabilization during minimally invasive coronary artery bypass grafting performed without cardiopulmonary bypass via a small (8 to 10 cm) left anterolateral thoracotomy. This device facilitates the anastomosis of the left internal mammary artery to the left anterior descending coronary artery on the beating heart. The device consists of a simple coronary stabilizer mounted on a wound spreader. We have used this device successfully in 35 primary minimally invasive coronary artery bypass grafting operations.

The internal mammary artery malperfusion syndrome: Late angiographic verification

Here we report our experience with the incidence and the surgical treatment of the internal mammary artery (IMA) malperfusion syndrome, evaluate the predictive role of previously described risk factors for the syndrome, and assess the late patency of IMA grafts in patients in whom an IMA malperfusion syndrome was diagnosed and treated by additional saphenous vein grafting of the left anterior descending coronary artery. From June 1992 to November 1995, 969 IMAs were anastomosed to the left anterior descending coronary artery system. In 11 patients, IMA malperfusion syndrome was diagnosed and treated by additional saphenous vein grafting of the LAD. There were 8 men and 3 women with a mean age of 58.9 years. The angiographic and clinical data for each patient were reviewed, and all but 1 surviving patient underwent late angiographic control (mean follow-up, 18 months; range, 4 to 46 months). One patient died in the hospital. No previously described risk factor was strongly associated with the occurrence of IMA malperfusion syndrome. Late angiography revealed a malfunctioning IMA graft in 7 of the 9 patients. A string sign was observed in 1 patient and a normally functioning IMA anastomosed to a diagonal branch not connected to the LAD, in another. In no patient was a widely patent and normally functioning IMA graft observed. In our series, a high proportion of IMA grafts were found to be malfunctioning at late angiography. This observation, in contrast to previous reports, suggests that IMA malperfusion syndrome can often be attributable to technical problems in harvesting the IMA or in performing the IMA anastomosis. Functional IMA insufficiency seems to play only a marginal role in determining the IMA malperfusion syndrome.

Improved Method for Direct Coronary Grafting Without CPB via Anterolateral Small Thoracotomy

We describe an improved method of minimally invasive coronary artery bypass grafting that facilitates the anastomosis on the beating heart by means of a rigid and simple coronary stabilizer. This technique permits anastomosis of the left internal mammary artery to the left anterior descending coronary artery through a small (8 to 10 cm) left anterolateral thoracotomy without cardiopulmonary bypass. We successfully used this technique in 20 primary coronary artery bypass grafting operations, without in-hospital mortality or any other cardiac complication.(Ann Thorac Surg 1997;63:567–9)

Coronary angiography and coronary artery by-pass grafts in diabetics

Angiographic data and findings at operation in 118 diabetics undergoing coronary artery bypass graft have been compared with those from 98 non-diabetic patients matched for sex and age. Atherosclerosis in the epicardial arteries in diabetics is more severe than in the general population. Saphenous vein grafting and internal mammary artery anastomoses are hampered by the fragility, irregularity, calcification and thickening as well as extensive atherosclerotic plaques in diabetic vessels. However, post-operative mortality and morbidity are no higher in diabetics and the length of hospitalisation is comparable with those of non-diabetics undergoing these procedures.

Sequential internal mammary artery grafting: a viable alternative in myocardial revascularization

The internal mammary artery has become the conduit of choice in myocardial revascularization. The expanded use of this ideal conduit for sequential grafting has enhanced its application. Between March 1985 and June 1993, 245 consecutive patients underwent revascularization of the myocardium with internal mammary artery bypass grafts with at least one sequential anastomosis. There were 186 men and 59 women, with a mean age of 65.1 (range 40–82) years. Unstable angina was present in 141 patients (57.6%) and 36 patients (14.7%) had left main coronary artery stenosis (>50%). Before surgery, five patients (2.0%) were in New York Heart Association (NYHA) class II, 113 (46.1%) in class III, and 127 (51.8%) in class IV. There were a total of 1041 coronary artery grafts, mean 4.2 (range 2–7) grafts per patient and 528 sequential left internal mammary artery anastomoses, mean 2.2 per patient. Hospital mortality rate was 2.4% (six patients). Almost two-thirds of the patients experienced no hospital complications. The most frequent complication included arrhythmia in 36 patients (14.7%), respiratory insufficiency in 15 (6.1)% and temporary left phrenic nerve palsy in ten (4.1%). Mean follow-up was 37.0 (range 1–94.2) months. The mean(s.e.m.) actuarial survival rate for patients discharged from hospital was 94.8(1.6)% at 36 months and 82.4(5.0)% at 72 months. At follow-up of 222 patients, 185 (83.3%) were symptom-free in NYHA class I and 27(12.2%) were in class II. Though technically demanding, multiple sequential internal mammary artery grafting is feasible and can be accomplished with low hospital mortality and morbidity. The added complexity, length of procedure and potential for inadequate volume flow through the application of sequential grafting did not adversely affect the clinical outcome in the series

Intraoperative Assessment of Internal Mammary Artery Bypass Graft Patency by Thermal Coronary Angiography

Following early graft failure in some patients during routine use of the internal mammary artery In coronary bypass surgery, a thermal coronary angiography technique was used for direct intraoperative control of internal mammary artery graft patency. This non-invasive method allows the evaluation of graft patency, anastomotic integrity and initial flow patterns without compromising the conduct of the surgical procedure. Internal mammary artery graft patency was controlled by thermal coronary angiography in 348 patients undergoing coronary bypass surgery. Graft anatomy, perfusion and distal run-off in the recipient native coronary artery was delineated by thermal coronary angiography using the temperature gradient of the warm perfusing blood and the cold myocardium. Thermal coronary angiograms were evaluated for graft and anastomotic patency as well as for direction and magnitude of internal mammary artery flow in the native coronarles. Some 348 internal mammary artery grafts, including 13 sequential grafts, were evaluated. Thermal coronary angiography failed for technical or logistical reasons in seven of 348 cases (2.0%). Thermal coronary angiography documented optimal anterograde flow in 282 of 341 cases (82.7%). reduced anterograde flow in 38 of 341 (11.1%) and no anterograde flow in 21 of 341 (6.2%). Using this approach 21 internal mammary artery graft occlusions were discovered, 18 at the anastomotic site and three at the site of the previously placed bulldog clamp. In addition, six unexpected distal native coronary stenoses and three Internal mammary artery graft spasms were detected by thermal coronary angiography and found to be responsible for impaired anterograde flow. Based on these findings, 16 anastomotic revisions, nine additional vein grafts and two additional vein patches were performed. Following revision, the patency of internal mammary artery anastomoses and of additional vein grafts was well documented by thermal coronary angiography in all but two cases; in these an additional vein graft was performed when revision of the internal mammary artery graft anastomosis proved ineffective. Thermal coronary angiography revealed an early internal mammary artery graft failure rate of 6.2%, caused by technical error in most cases. Thermal coronary angiography findings led to immediate, low-risk revision and affected intraoperative decision making in 7.9% of patients. Analysis of internal mammary artery graft failures demonstrated a lower incidence of technical errors among experienced surgeons. In conclusion thermal coronary angiography is an easy-to-use. intraoperative, non-invasive method of assessing internal mammary artery graft patency.

Conjoined Double Internal Mammary Artery Grafting

Double internal mammary artery (IMA) grafting to the coronary arteries was performed on 82 patients. In ten of them one IMA was used as a free graft, and was proximally connected to the other ("conjoined" double IMA), the indications being insufficient supply of adequate veins, diseased aortic wall, availability of only a short right IMA segment for free grafting, occluded left subclavian artery, and when distal and scattered lesions of relatively important vessels had to be bypassed. Additional sequential IMA anastomoses were performed in four patients and an additional sequential vein graft in a fifth. All patients became angina-free postoperatively and have remained so during observation up to 16 months. Recatheterization studies were performed in six patients and in all of them the IMA-to-IMA (n = 6) and distal anastomoses (n = 26) were patent. Conjoined double IMA grafting is an important option available to the cardiac surgeon for management of selected patients with coronary artery disease.

Tachycardia and coronary blood flow: non-invasive estimation during Valsalva manoeuvre and exercise.

Simultaneous changes in cycle length and coronary blood flow were studied during Valsalva manoeuvre and supine cycloergometer exercise test in 10 male patients (mean age 48 +/- 12 years) who had successfully undergone myocardial revascularization by surgical anastomosis of the left internal mammary artery on the left anterior descending coronary artery. Blood velocity curves in the left internal mammary artery were obtained by a non-invasive continuous-wave Doppler probe at rest, in the last phase of the expiratory effort of the Valsalva manoeuvre and at the maximum load attained during the exercise test. Mean arterial pressure by sphygmomanometer, and cardiac cycle length on the basis of Doppler recording were measured. Mean blood velocity, the length of the blood column entering the coronary bed at each cycle (cardiac cycle times mean velocity), an index of blood cell acceleration (the ratio of mean velocity to cardiac cycle), and an index of coronary resistance (the ratio of mean pressure to mean velocity), were calculated. For approximately the same change in cycle length, coronary resistance decreased in exercise, with an increased mean velocity, but increased in Valsalva, with no changes in mean velocity. The length of the blood column entering the coronary bed at each cycle was unchanged in exercise, with a marked increase in the acceleration index, while it decreased in Valsalva. Therefore, we hypothesize that tachycardia has a limiting effect on sympathetic coronary constriction in Valsalva when cardiac external work is decreased, and an additional vasodilatory effect on coronary bed in exercise when external work is increased.

Anomalous origin of the left coronary artery

Children with anomalous origin of the left coronary artery from the pulmonary artery are at risk for myocardial infarction and death. Surgical management of this condition in children has evolved significantly during the past 20 years. Between 1970 and 1990, a total of 20 of these patients underwent surgical intervention at two institutions. Age at operation ranged from 3 weeks to 11 years (mean, 26 months). Twelve patients had congestive heart failure, three were in cardiogenic shock, and two had cardiac murmurs. Operative techniques included ligation (n = 9), subclavian artery anastomosis (n = 5), aortic implantation (n = 3), internal mammary artery anastomosis (n = 1), intrapulmonary tunnel from aortopulmonary window to coronary artery (n = 1), and cardiac transplantation (n = 1). The three deaths in the series occurred at 3 weeks, at 2 months, and at 9 years after ligation. There have been no deaths after establishment of a two coronary artery system or after transplantation. Two of the five patients who had subclavian artery anastomosis to the anomalous coronary artery have severe anastomotic stenosis and collateralization. For patients with anomalous origin of the left coronary artery from the pulmonary artery, we recommend direct aortic implantation of the anomalous coronary artery at the time of diagnosis. Intrapulmonary tunnel from aortopulmonary window to coronary artery, or aorta-coronary bypass with internal mammary artery are recommended for children in whom aortic implantation is not anatomically feasible. Left coronary artery ligation is not indicated for these patients; those who have survived ligation should be considered for elective establishment of a two coronary artery system because of the risk of late death.

Internal Mammary Coronary Artery Anastomosis by Co2Laser: An Acute Experimental Study

This study was designed to determine the feasibility of anastomosing the internal mammary artery (IMA) and coronary artery with a carbon dioxide laser in a canine model. Twenty-two mongrel dogs were randomly assigned to two groups: group I (n = 11) underwent laser-assisted vascular anastomosis (LAVA) of the left IMA to the left anterior descending (LAD) coronary artery, whereas in group II (n = 11) the anastomosis was done with the conventional technique (handsewn). Laser methodology was used to micro-weld vessels utilizing a power of 200 mW with a spot size of 500 mu, producing an effective power density of 102 W/cm2 and energy fluence of 9,172 joules/cm2 in a continuous mode at a distance of 2 cm. The short-term patency rate, measured at 2 hours after completion of the anastomosis, was 100% in both groups. The time required to perform the LAVA in group I was significantly shorter than group II (6.27 +/- 0.47 vs 11.6 +/- 0.67 min, p less than 0.05). The mean anastomotic bursting pressure in group I was significantly lower compared to group II (348 +/- 8 vs 402 +/- 9 mmHg, p less than 0.05). Histologic evaluation of all vessels showed moderate thermal injury of the adventitia and media in the laser group. Scanning electron microscopy exhibited a smooth anastomotic area in group I, whereas endothelial and perianastomotic changes with multiple needle craters occurred in group II (conventional anastomosis).(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of postoperative comlications between saphenous vein and IMA grafts to left anterior descending coronary artery

Considerable controversy exists regarding relative morbidity associated with the saphenous vein graft (SVG) and internal mammary artery (IMA) graft in patients undergoing myocardial revascularization. As a part of the cooperative study on use of antiplatelet drugs for graft patency, operative and postoperative data were prospectively collected on 1,150 patients who underwent either SVG (n = 656) or IMA anastomosis (n = 494) to the left anterior descending coronary artery. There were no differences in baseline characteristics of patients, distribution of randomization among treatment groups, and total number of distal anastomoses performed between the two groups. The aortic cross-clamp time, cardiopulmonary bypass duration, operative time, and chest tube drainage were greater (p = 0.0001) in the patients with IMA grafts compared with SVG. However, there was no difference in the operative mortality rate, the amount or blood and blood products received, the reoperation rate for control of postoperative bleeding, and incidence of wound complications between the two groups. The early and 1-year patency rates for the IMA were slightly but not significantly better than the SVG patency rates (92.8% versus 90.1% for 1-year patency; p = 0.309). In conclusion, use of IMA is associated with a longer operative time as well as increased postoperative bleeding compared with the SVG. It, however, does not increase operative mortality or postoperative morbidity.

Iatrogenic Internal Mammary Artery to Coronary Vein Fistula

Iatrogenic aortocoronary vein fistula following coronary artery bypass surgery is a rare complication. We describe the first reported case of inadvertent anastomosis of the left internal mammary artery to cardiac vein. The clinical characteristics and consequences as well as the angiographic characteristics of this fistula are described. Precautions that may be taken to prevent this complication are also addressed.

Catastrophic consequences of internal mammary artery hypoperfusion

Inappropriate use of the internal mammary artery for complex coronary artery bypass operations may have disastrous yet avoidable consequences. In 712 consecutive coronary artery bypass operations performed between January 1985 and September 1986, five patients had an intraoperative course suggesting internal mammary artery hypoperfusion. In three, coronary artery bypass was performed as a reoperative procedure. The following similarities were noted in all five patients: a technically satisfactory internal mammary artery anastomosis, a left anterior descending coronary artery having critical proximal stenosis (greater than or equal to 90%), a distal artery at least 2.0 mm diameter free of disease, satisfactory left ventricular function, a catastrophic clinical outcome (death in three, cardiac transplantation in one, 3-month hospitalization in one), and all patients could be weaned from cardiopulmonary bypass only after insertion of a saphenous vein graft distal to the internal mammary artery graft. Bilateral internal mammary grafts were used in four of five patients. In both patients without prior coronary artery bypass, there was a discrepancy in internal mammary artery flow and myocardial demand: cardiac hypertrophy, large (2.5 mm) distal left anterior descending supplied by a small (less than 2.0 mm) internal mammary artery, and sequentially grafted arteries. All three patients having reoperative coronary artery bypass had normal anterior wall motion, and in two of the three patients, the left anterior descending-saphenous vein graft was arteriographically normal and the sole source of blood to the anterior, septum, and inferior myocardium. In two patients the normal left anterior descending-saphenous vein graft supply a large left anterior descending (greater than 2.0 mm) was replaced with a small left internal mammary artery. Internal mammary artery hypoperfusion typically occurred 30 to 40 minutes after discontinuation of cardiopulmonary bypass but was also seen in the intensive care unit. The condition may be confused with internal mammary artery or coronary artery spasm. It may be avoided by careful prebypass planning of the operation, intraoperative assessment of internal mammary artery flow and size with prudent use of sequential internal mammary artery grafting, avoiding use of the terminal left anterior descending (unless large), retaining nonobstructed saphenous vein grafts when the internal mammary artery has marginal flow or size, and placement of a saphenous vein graft distal to the left internal mammary artery when size or flow in the latter is small.

Sequential mammary grafting: Bound volumes available to subscribers Clinical, functional, and angiographic assessment 6 months postoperatively in 231 consecutive patients

Between September 1985 and November 1987, 246 sequential mammary grafts were performed in 231 consecutive patients. Seventy-eight percent had triple vessel disease, and 33% required an urgent procedure. The length of the internal mammary artery pedicle was the only limitation to its use. No account was taken of the free cut-end flow of the internal mammary artery. There were 14 bilateral sequential mammary grafts and 15 free sequential mammary grafts. Of the 531 sequential mammary anastomoses, 482 were built with the left internal mammary artery; 113 (21%) were diamond-shaped anastomoses. The right internal mammary artery was brought through the transverse sinus in 44 cases, 10 times for sequential grafting of circumflex branches. Taking into account the adjunctive venous anastomoses and the single internal mammary artery anastomoses, there were 4.5 distal anastomoses per patient, 2.8 being mammary anastomoses and 2.3 being sequential mammary anastomoses. The hospital mortality rate was 2.6%. The prevalence of perioperative myocardial infarction was 5.2%. Follow-up was complete and averaged 15.4 months. Six patients (2.7%) still had angina pectoris. One hundred fifty-seven (71%) patients were recatheterized 6 months after the operation, and 95% of the sequential mammary anastomoses were still patent. The patency rate of the diamond-shaped mammary anastomoses was 94.5% and that of the anastomoses corresponding to the right internal mammary arteries brought through the transverse sinus was 94.3%. The gratifying functional results (maximal stress test combined with exercise thallium scintigraphy) obtained at an average of 6 months postoperatively illustrated the surprising physiologic adaptability of the internal mammary artery. As the attrition rate of the mammary artery grafts beyond 6 months postoperatively is thought to be minimal, gratifying long-term results with widespread use of sequential mammary grafts can be anticipated.

Deleterious effects of shock in internal mammary artery anastomoses

Internal mammary arteries (IMAs) are increasingly used for coronary artery revascularization. However, spastic reactions alter IMA-coronary artery anastomoses have been reported. Internal mammary artery flow and the effects of sudden hypovolemia, gradual hypovolemia, papaverine hydrochloride, nitrates, and epinephrine were evaluated in a canine model (n = 10) (body weight, 19 ± 5 kg) without interference from coronary artery resistance by dissecting the IMA as a pedicle, calibrating the flowmeter during free IMA flow, and anastomosing the IMA to the right atrium. Sudden hypovolemia (withdrawal of 20% of circulating blood volume over 90 seconds) caused significant modifications ( p < 0.01) of the following hemodynamic variables: heart rate (+12%), right atrial pressure (−17%), pulmonary artery pressure (−20%), wedge pressure (−30%), aortic pressure (−49%), cardiac output (−33%), distal IMA pressure (−54%), and IMA flow (−85%). During hypovolemia, IMA flow could not be increased with topical application of papaverine, but baseline values were achieved after retransfusion of the withdrawn blood volume. Gradual hypovolemia and application of large doses of nitrates showed less dramatic effects, and injection of an epinephrine bolus under rormovolemic conditions increased aortic pressure and IMA flow. Under sever hypovolemia, however, administration of an epinephrine bolus provoked only a minimal increase in aortic pressure and a contrasting decrease in IMA flow. We conclude that sudden, severe hypovolemia can lead to disproportionate IMA flow reduction and that pharmacological interventions are delicate under these circumstances.

Vasilii I. Kolesov: A pioneer of coronary revascularization by internal mammary-coronary artery grafting

Vasilii I. Kolesov, a cardiac surgeon from Leningrad, performed the first sutured internal mammary artery-coronary artery anastomosis on Feb. 25, 1964. He used the internal mammary artery pedicle (Kolesov's pedicle, Feb. 25, 1964) and described beadlike nodules and a dimpling of the epicardium over the atherosclerotic coronary artery (Kolesov's groove sign, Jan. 26, 1965). He introduced mechanical suturing to coronary artery surgery (March 22, 1967), internal mammary artery grafting for acute myocardial infarction (Feb. 5, 1968) and for unstable angina (May 17, 1968), and retrograde (Dec. 11, 1968) and bilateral (July 10, 1969) internal mammary artery grafts. Kolesov demonstrated early and long-term clinical and hemodynamic improvement with a 70% survival rate at 5 to 17 years' follow-up after internal mammary artery grafting (1967 to 1987).

Use of the internal mammary artery in myocardial revascularization

Internal mammary artery-coronary artery anastomosis is currently considered the newest and best technique for surgical revascularization of ischemic myocardium. The origin and evolution of this technique are reviewed.

内胸動脈‐冠動脈吻合法の検討 結節縫合と連続縫合の比較

内胸動脈‐冠動脈吻合法の検討 結節縫合と連続縫合の比較

Pericardial Flap to Minimize Internal Mammary Artery Anastomotic Tension

A technique is described that decreases tension on the left internal mammary artery anastomosis in patients whose lungs have herniated across the midline.