Subaortic obstruction and the Fontan operation

Systemic outflow tract obstruction in the heart with a functional single ventricle promotes myocardial hypertrophy, and this has been shown to be an unequivocal risk factor for poor outcome at Fontan procedure. Such systemic outflow tract obstruction may be congenital or acquired. Those factors contributing to acquired systemic outflow tract obstruction in those patients with a double-inlet left ventricle, a rudimentary right ventricle, and a discordant ventriculoarterial connection include the size of the ventricular septal defect, previous pulmonary artery banding, and other volume unloading surgical procedures. Staging with a bidirectional cavopulmonary connection and construction of a proximal pulmonary artery-aortic connection or ventricular septal defect enlargement has neutralized this factor.     

Variation in the size and distensibility of the pulmonary arteries in d-transposition of the great arteries

The relative size of the main pulmonary artery was determined from cineangiograms of 117 patients with d-transposition of the great arteries by calculating the ration between the diameters of the main pulmonary artery and aorta. The pulmonary artery was largest in patients with ventricular septal defect or patent ductus arteriosus, or both, because of increased pulmonary arterial pressure and flow. In patients with an intact ventricular septum or with left ventricular outflow tract obstruction, or both, the main pulmonary artery was approximately the size of the aorta. Two cases of d-transposition and gross dilatation of the main pulmonary artery and hypoplastic first branch pulmonary arteries are presented. In these cases the ratio between the diameters of the main pulmonary artery and aorta was greater than in any of the other 117 cases studied...     

Myocardial infarction complicated by ventricular septal rupture in a patient with polycythemia vera and minimal coronary ectasia

Although it is known that patients with polycythemia vera (PV) are at increased risk of myocardial infarction (MI) secondary to thrombosis, ventricular septal rupture in this setting has never been reported. Ventricular septal rupture complicating a small anteroseptal MI is reported in a patient with PV and with only minimal ectasia of the left anterior descending coronary artery. Despite small infarct size these patients may be predisposed to myocardial hemorrhage, increasing the likelihood of myocardial rupture.     

Atopic dermatitis and related factors observed at infant physical examination at health centers

OBJECTIVE: To evaluate the clinical usefulness of cardiac SPECT in the detection of coronary artery disease, and the relation with the site, number and severity of the angiographic lesions. METHOD: We studied 216 patients; with myocardial perfusion imaging with SPECT (T1-201 and/or Tc-99 Sestamibi) and coronary angiogram. We defined the localization of myocardial perfusion defects (anterior, inferior, septal, lateral or apex), and their correlation with coronary angiogram, based on the location, number and severity of coronary angiographic lesions. We considered significative coronary stenosis obstructions of 60% or more. RESULTS: Of the 216 patients studied, 181 (83.8%) were male and 35 (16.2%) female. Age ranged between 30 and 82 years; 143 males and 23 females had a previous myocardial infarction. The SPECT sensitivity for diagnosing ischemia of one, two and three vessel disease was 94%, 96% and 100%. The sensitivity for diagnosing disease in specific vascular territories was 91.6% for LAD 100% for RCA, 92.8% for CX and 100% for left main. CONCLUSIONS: Myocardial perfusion imaging with SPECT has high sensitivity for diagnosing coronary artery disease. The sensitivity and specificity were more accurate in proximal anterior descending artery disease, left main and three-vessel coronary artery disease. We found correlation in the site, number and severity of the angiographic lesions and in myocardial perfusion defects.     

Interventricular septal motion in patients with proximal and distal left anterior descending coronary artery lesions

In order to evaluate the ability of the echocardiogram to detect and localize left main or left anterior descending (LAD) coronary artery lesions, 43 patients were studied. The systolic excursion of the left side of the septum and the ratio of posterior wall to septal excursion were measured. Seventeen patients had no LAD lesions; all had systolic septal excursion of 3 mm or greater. Twelve patients with septal excursion of 2 mm or less all had left main or LAD lesions, but 14 other patients with LAD lesions had septal excursions of 3 mm or greater. Nine of 16 patients with LAD lesions proximal to the first septal branch had reduced or absent septal excursion, as did three of ten with LAD lesions distal to the first septal branch. In a setting of coronary artery disease reduced or absent septal motion on echocardiography suggests involvement of the left main or left anterior descending coronary. However, the technique is relatively insensitive, with 54% of the LAD patients having normal septal motion.     

Anomalous right coronary artery from the pulmonary artery in Taussig-Bing anomaly

The presence of associated anomalies in patients with double-outlet right ventricle can significantly alter surgical intervention. Preoperative delineation of these anomalies can facilitate surgical planning and improve outcome. We describe a case in which the right coronary artery and anterior descending coronary artery arose from the pulmonary artery in a patient with double-outlet right ventricle with subpulmonary ventricular septal defect (Taussig-Bing anomaly). Recognition of this important anomaly prevented significant intraoperative myocardial damage by altering techniques of cardioplegia administration for myocardial preservation.     

Angina caused by subclavian-coronary steal in patients revascularized with internal mammary artery]

After coronary bypass surgery in the left internal mammary artery, occlusive atherosclerosis in the proximal subclavian artery can produce reverse flow in the mammary artery and myocardial ischemia (coronary-subclavian steal syndrome). This is a rare cause of recurrent myocardial ischemia. We present two patients with postoperative complete obstruction in the proximal subclavian artery and inverse flow in the mammary artery producing severe ischemia in the left anterior descending artery territory. Both patients were treated with subclavian-subclavian bypass, which in one patient was ineffective in producing an adequate anterograde flow in the left internal mammary artery. We review clinical management, diagnostic methods and therapeutic options used in the coronary-subclavian steal syndrome.     

Post-traumatic ventricular septal defect following coronary bypass surgery

A 60-year-old patient underwent triple coronary artery bypass grafting following an inferoseptal myocardial infarction and early onset of exertional angina. Four years later he was involved in a car accident during which he sustained an abdominal and thoracic trauma. Approximately 1 month after discharge, a ventricular septal defect was diagnosed by two-dimensional Doppler echocardiography with patency of all grafts at coronary angiography. Closure of the septal defect was successfully accomplished through a right atrial approach. Rupture of the ventricular septum following blunt chest trauma in a patient with previous myocardial revascularization has not been previously reported.     

Ischemia-associated intraventricular conduction disturbances during exercise testing as a predictor of proximal left anterior descending coronary artery disease

To determine the incidence and significance of transient intraventricular conduction abnormalities occurring in association with myocardial ischemia during exercise testing, the recordings of 2,200 consecutive exercise tests were reviewed. Ten patients (0.45%) were identified as having both ischemia and intraventricular conduction abnormalities that developed transiently during the exercise test. In all 10 patients both typical angina and electrocardiographic evidence of ischemia developed during exercise. Among the 10 patients, left anterior hemiblock developed in 4, left posterior hemiblock in 2, right bundle branch block (RBBB) in 2, RBBB with left axis deviation in 1, and left anterior hemiblock progressing to complete left bundle branch block (LBBB) in 1. All 10 patients had cardiac catheterization showing significant obstruction of the left anterior descending (LAD) coronary artery at or before the origin of the first septal branch. Eight patients were treated surgically and 2 medically, all with relief of ischemic symptoms. Nine of the 10 had repeat exercise stress testing without angina or electrocardiographic evidence of ischemia and without recurrence of the transient intraventricular conduction disturbance. It is concluded that the development of transient intraventricular conduction abnormalities associated with myocardial ischemia during exercise testing is an uncommon occurrence (0.45%). When such conduction disturbances do develop, the existence of significant disease in the proximal portion of the LAD coronary artery is strongly suggested. With control of myocardial ischemia, the transient conduction disturbances during exercise are ameliorated.     

Subpulmonary obstruction in congenitally corrected transposition of the great arteries due to ventricular membranous septal aneurysms

The clinical, hemodynamic, and angiographic observations, as well as the surgical approach used for repair in three patients with congenitally corrected transposition of the great arteries and ventricular membranous septal aneurysms, are presented. In two of the three patients the membranous septal aneurysm caused subpulmonary obstruction, with 94 and 125 mm Hg systolic gradients. In each patient the aneurysm was demonstrated by angiocardiography, which also showed differences in size and shape with cardiac systole and diastole. Review of the previously described reports indicates that patients with congenitally corrected transposition often display various forms of pulmonary outflow obstruction and when a ventricular membranous septal aneurysm exists, a significant subpulmonary obstruction is present in most patients. The unique anatomic relationship between the pulmonary artery and a ventricular membranous septal aneurysm in patients with transposition of the great arteries with and without atrioventricular discordance explains why subpulmonary obstruction sometimes develops.     

Anatomic observation of the dorsal metacarpal arteries

Anastomosis between the first to the fourth dorsal metacarpal arteries was observed in 43 hands of adult corpses. It was found that 86% of the first dorsal metacarpal artery arises from the radial artery, 14% is replaced by the main artery of thumb or superficial branches of the radial arteries; eighty-six percent of the second dorsal metacarpal artery originates from the dorsal carpal artery. Sixty-seven percent of the third and the fourth dorsal metacarpal arteries is formed by anastomosis of the dorsal carpal artery and its deep palmar arch. The first to the fourth dorsal metacarpal arteries have 4 to 8 cutaneous branches and proximal and distal anastomoses. It is concluded that the dorsal metacarpal arteries are characterized with multiple sources and abundant anastomoses around the metacarpophalangeal joints, which can be used with advantage in the repair of soft tissue defects of the area.     

Enhanced detection of proximal right coronary artery stenosis with the additional analysis of right ventricular thallium-201 uptake in stress scintigrams

The value of right ventricular thallium-201 analysis in detecting proximal right coronary artery stenosis in exercise myocardial scintigraphy was analyzed in 52 patients, 27 with and 25 without proximal right coronary artery stenosis. For the detection of proximal right coronary artery stenosis, the sensitivity and specificity of thallium scintigraphic analysis were 59 and 88% for a right ventricular abnormality, 67 and 68% for a left ventricular inferior wall abnormality, and 93 and 56% for an abnormality of either. When both right and left ventricular thallium images were abnormal, all 9 patients had proximal right coronary artery stenoses, and when both were normal, 26 of 28 patients had a normal proximal right coronary artery. The sensitivity and specificity of blood pool scintigraphic variables during exercise (right ventricular ejection fraction and left ventricular inferior wall motion) were not significantly different for detection of proximal right coronary artery stenosis. Thus, the additional analysis of the right ventricle on thallium-201 stress scintigrams can improve the detection of proximal right coronary artery stenosis. When both right ventricular and left ventricular thallium scintigrams are abnormal (or normal), the ability to predict the presence (or absence) of proximal right coronary artery stenosis is very high.     

Atherosclerosis of the inferior epigastric and internal mammary arteries

Atherosclerosis of the inferior epigastric artery (IEA) and the internal mammary artery (IMA) was evaluated in 21 patients with coronary heart disease. Both arteries were used simultaneously in coronary artery bypass grafting. Histologic samples were obtained from the proximal and distal segments of IEA and from the distal segment of IMA. Morphologic findings in regard to atherosclerosis were classified semiquantitatively as normal (0), or luminal narrowing <25% (1), 25-50% (2) or >50% (3), or as overt atherosclerosis and calcification (4). Atherosclerosis was absent or minimal (1) in distal samples from both arteries. Only one IMA showed moderate (2) luminal atherosclerotic obstruction. Two samples from proximal IEA showed moderate (2) or severe (4) atherosclerotic changes which limited their use as free grafts. These finding suggest that atherosclerosis is minimal and comparable in distal IEA and IMA in their natural environments even in patients with coronary heart disease. The long-term effect of aortic pressure on free IEA graft is still unclear.     

Anomalous origin of the right coronary artery from the left anterior descending coronary artery

A 77-year-old male presented with a recent posterior myocardial infarction for coronary angiography. This angiogram revealed a rare, previously unreported anomalous origin of the right coronary artery from the proximal left anterior descending coronary artery distal to the first major diagonal branch.     

Spectrum of coronary arterial spasm. Clinical, angiographic and myocardial metabolic experience in 29 cases

A relationship of coronary arterial spasm to variant angina pectoris, subendocardial ischemia, major ventricular arrhythmias and myocardial infarction has been demonstrated. In 29 patients, spasm was angiographically observed in normal-appearing coronary arteries (7 patients) as well as superimposed on various degrees of coronary atherosclerotic obstruction (22 patients). All patients experienced an atypical anginal syndrome;16 patients also experienced typical exertional angina. Coronary spasm appeared to be a major contributory factor in eight occurrences of myocardial infarction and in 11 incidents of ventricular tachycardia, ventricular fibrillation and heart block. Coronary spasm in the 29 cases was distributed in the following fashion: left main trunk, 6 cases; right main trunk, 12 cases; proximal left anterior descending artery, 13 cases; proximal circumflex artery, 1 case; distal left anterior descending artery, 1 case; and distal circumflex artery, 2 cases. In 5 cases coronary spasm was noted at multiple sites.     

Interstitial ectopic pregnancy--management with laparoscopically-guided local methotrexate infiltration

We report a case of complete heart block (CHB) and polymorphic ventricular tachycardia (VT) which was associated with a modest-sized myocardial infarction (MI) following incidental occlusion of the first septal perforator (FSP) branch after stent deployment to the left anterior descending (LAD) coronary artery. These complications were successfully treated with temporary pacing and subsequently resolved with spontaneous recanalization of the first septal perforator. This case represents an interesting product of medical progress which defies the adverse natural history and poor prognosis of anteroseptal MI associated with CHB due to the small amount of myonecrosis associated with this event.     

Incidence of right ventricular asynergy in patients with coronary artery disease

The effects of coronary artery disease on patterns of left ventricular contractility have been thoroughly investigated. In contrast, little is known about the incidence of right ventricular dysfunction induced by this disease. To evaluate the frequency of right ventricular asynergy, biplane right ventricular cineangiograms were obtained in 26 patients. Seven segmental axes of shortening were analyzed in each end-systolic and end-diastolic frame and normalized as percent decrease (or increase) in axis from end-diastolic length. Of 26 patients, 8 (Group I) served as normal (control) subjects. The remaining 18 patients had significant coronary artery disease; 6 of these (Group II) had no significant disease of the right coronary artery, whereas 12 (Group III) had significant obstruction of this artery. Four patients in Group II had a previous anteroseptal myocardial infarction, and six in Group III had a previous inferior myocardial infarction. There was a progressive decrease in segmental axes of shortening from Group I to II and from Group II to II, but the decrease was not significant at the level P less than 0.01. Only one patient in Group II had frank dyskinetic segmental motion of the interventricular septum (this patient had had a previous anteroseptal myocardial infarction), whereas two patients in Group III had dyskinetic segmental motion of the free right ventricular wall (both had previous inferior myocardial infarction). Therefore, coronary artery disease seldom produces significant right ventricular asynergy. Abnormal septal motion is associated with previous anteroseptal myocardial infarction; however, dyskinetic motion of the free right ventricular wall occurs only in patients with a right coronary arterial lesion and previous inferior myocardial infarction.     

Anatomic variations of the coronary arteries

PURPOSE: To study the coronary arteries and their main branches showing the aspects of source, trajectory and anastomoses of these vessels at the subepicardial level. METHODS: The study was carried out on 110 adult human hearts, of both sexes, fixed in 10% formaldehyde solution. The pericardium was removed to expose the coronary arteries and their branches at the subepicardial level. RESULTS: In 38.18% of the cases the left coronary artery presented a trifurcation into anterior interventricular, circunflex and left marginal branches (35.70%) and into anterior interventricular, circunflex and lateral branches (64.30%). In 60% of the hearts examined, the left coronary artery presented a bifurcation into anterior interventricular and circunflex branches. In 1.82% of the cases these two branches arise directly from the aorta. An anastomosis, at the subepicardial level, between the anterior and posterior interventricular branches was observed in 56.36% of the hearts. In 88.18% the posterior interventricular branch arised from the right coronary artery, whereas in 11.82% this vessel arises from the circunflex branch. Anastomoses between the right coronary artery and the circunflex branch were found in 10% of the hearts (crux cordis). The dominance of the right coronary artery was present in 69.09% of the cases, of the left coronary artery in 11.82% and in 19.09% of the hearts had balanced distribution. CONCLUSION: The coronary arteries and their main branches present a great quantity of variations with regard to source, trajectory and anastomoses. This knowledge is important for the interpretation of coronary angiography and surgical myocardial revascularization.     

Myocardial bridge of the coronary arteries and its clinical significance

Myocardial bridge is a congenital anomaly of the coronary artery and appears on an angiogram as a systolic narrowing. Major coronary veins are rarely covered by myocardial bridges. The functional significance of coronary bridging remains controversial. Generally, bridging is not though to result in symptoms, as the coronary narrowing occurs during systole and most coronary flow occurs during diastole. Some authors reported this condition in association with angina pectoris, myocardial infarction, cardiac arrhythmias and sudden cardiac death. The mechanism of ischemia, connection with atherosclerosis are not clear. The symptomatic compressive myocardial bridge is in itself an indication for operation by simple section of the bridge. But if there exist associated atheromatous lesions, the surgeon should combine aortocoronary bypass with section or coronary angioplasty.     

Results of rapid two-stage arterial switch operation in patients with transposition of the great arteries: one-year postoperation

The rapid two-stage arterial switch operation is an alternative therapy for patients with simple transposition of the great arteries who present beyond the neonatal period and have low left ventricular pressure. It provides normal ventricular function compared to the atrial switch operation. Between July 1994 and February 1997, there were 13 such infants who had rapid two-stage arterial switch operation performed at Siriraj Hospital. There was 1 late death (11 months after the operation). All 12 survivors (mean age 22.4 +/- 5.7 months) were clinically evaluated and had echocardiography performed at 14.8 +/- 4.9 months after the operation. All were asymptomatic. Echocardiogram revealed a residual small atrial septal defect (1 case), small ventricular septal defect (1 case), mild supravalvar neopulmonary stenosis (2 cases), bicuspid neoaortic valve without stenosis (2 cases), dilated neoaortic sinus of Valsalva (6 cases, 50%) and mild neoaortic insufficiency (11 cases, 91.7%). The left ventricular function was hyperdynamic after pulmonary artery banding and significantly decreased to normal level at the time of study (shortening fraction of 43.8 +/- 10.7 vs 29.2 +/- 3.8%, respectively, p = 0.0005). The wall thickness was significantly increased after pulmonary artery banding and decreased overtime (0.48 +/- 0.08 vs 0.32 +/- 0.05 cm, respectively, p < 0.0005). The left ventricular dimension was significantly increased both after pulmonary artery banding and at the time of study (2.06 +/- 0.42 vs 3.32 +/- 0.30 cm, respectively, p < 0.0005). The left ventricular mass was significantly increased after pulmonary artery banding and at the time of study (21.79 +/- 7.79 vs 33.08 +/- 7.40 g/m2, respectively, p = 0.0005). The mortality and morbidity of rapid two-stage arterial switch operation are low. However, long-term follow-up should be monitored.