Restoration of patency of left internal mammary artery graft with progression of the underlying left anterior descending coronary artery disease

The use of the left internal mammary artery (LIMA) to graft a borderline lesion in the left anterior descending coronary artery (LAD) has been associated with distal narrowing and occlusion of the LIMA. We present a patient in whom the LIMA occluded 1 year after coronary artery bypass, but was found to be fully patent 4 years later, after progression of the native LAD disease. Cathet. Cardiovasc. Diagn. 42:213–215, 1997. © 1997 Wiley-Liss, Inc.     

Assessment of left internal mammary artery graft patency by transthoracic Doppler echocardiography

BACKGROUND: The successful application of noninvasive Doppler spectrum analysis has been reported for the hemodynamic assessment of LIMA graft after myocardial revascularization. HYPOTHESIS: The objective of this study was to assess the utility of transthoracic Doppler echocardiography (TTE) in providing information on LIMA flow in patients after coronary artery bypass graft surgery. METHODS: In all, 22 patients (aged 62 +/- 8 years) with LIMA graft to the left anterior descending (LAD) coronary artery who underwent coronary angiography were assessed using high-frequency (5 MHz) transthoracic Doppler echocardiography. They were compared with 25 patients with angina (control group A, aged 59 +/- 12 years), in whom an ungrafted LIMA was assessed, and with 17 patients (control group B, aged 59 +/- 9 years) with angiographically normal coronary arteries, in whom the LAD was assessed. RESULTS: A biphasic pattern (systolic and diastolic) was recorded in all cases. In 14 patients with a normal graft or < 70% stenosis (Group 1) and in control group B, blood flow was maximal during diastole. In eight patients with severe graft stenosis > 70% (Group 2) and control group B, blood flow was maximal during systole, with low diastolic flow. The diastolic fraction of the velocity time integrals was 0.81 +/- 0.11 for Group 1 and 0.25 +/-0.06 for Group 2 (p < 0.05). A diastolic velocity time integral fraction < 0.5 predicted > 70% stenosis with a sensitivity and specificity of 100%. The ratio of systolic/diastolic peak velocities was 0.61 +/- 0.31 for Group 1 and 3.21 +/- 0.49 for Group 2 (p < 0.05). A systolic/diastolic peak velocity > 1 predicted stenosis > 70% with a sensitivity and specificity of 100 and 90%, respectively. CONCLUSIONS: High-frequency TTE is a useful noninvasive method for detecting LIMA graft blood flow. Severe graft stenoses exhibited Doppler velocity patterns, which were different from those of patent grafts, or grafts with moderate stenoses.     

Communication between a nongrafted left internal mammary artery and left anterior descending coronary artery following saphenous vein bypass grafting

A case is described in which a pericardial branch of a nongrafted left internal mammary artery communicated directly with the distal left arterior descending artery, following saphenous vein bypass grafting. This type of collateralization following coronary artery bypass surgery seems to be very rare, and perhaps could protect the myocardium from severe ischemia. Cathet. Cardiovasc. Diagn. 40:170–172, 1997. © 1997 Wiley-Liss, Inc.     

Feasibility of measuring coronary flow velocity and reserve in the left anterior descending coronary artery by transthoracic Doppler echocardiography in a relatively obese American population

BACKGROUND: Transthoracic Doppler echocardiography (TTDE) assessment of coronary flow velocity reserve (CFVR) has been validated in Asian and European centers. This methodology has not gained acceptability in the United States due to the bias that coronary flow velocity (CFV) by TTDE might be difficult in an obese population with relatively poor acoustic windows. METHODS: Baseline CFV in the left anterior descending coronary artery (LAD) by TTDE was obtained in 67 nonselected American patients. A subset of 38/67 received adenosine infusion for measuring CFVR of the LAD. PURPOSE: The aim of this study was twofold: (1) to determine the feasibility of measuring CFV and CFVR in the LAD by TTDE in a relatively obese American population, and (2) to compare CFV and CFVR values in this population with those previously obtained in a group of Japanese patients. RESULTS: The mean body mass index (BMI) of the American population (28 +/- 6 kg/m2, range: 18-46 kg/m2) was significantly higher than that of the Japanese group (23 +/- 4 kg/m2, range: 15-37 kg/m2). Twenty-five American patients were classified as obese (BMI >30 kg/m2). Baseline CFV was obtained in 60/67 patients (feasibility: 90%) with a 10% need for intravenous contrast agent to enhance the delineation of the CFV envelope. The success rate in recording CFVR in American patients (92%) was nearly identical to that of a Japanese group (99%). The time-averaged peak diastolic coronary flow velocity increased from 15.6 +/- 5.5 cm/sec at baseline to 47.1 +/- 17.9 cm/sec during adenosine infusion, and CFVR was calculated to be 3.22 +/- 1.15 (range: 0.94-5.69). Intraobserver and interobserver variability for the CFV recording was 4.7 and 6.2%, respectively. CONCLUSIONS: These results suggest that the noninvasive measurement of CFV and CFVR of the LAD is feasible even in a relatively obese American population. Furthermore, the success rates for recording CFV and CFVR are similar to those measured in a Japanese population. This methodology has the potential to provide useful physiological information on the coronary circulation in American patients.     

Simultaneous transesophageal Doppler assessment of coronary flow reserve in the left anterior descending artery and coronary sinus allows differentiation between proximal and non-proximal left anterior descending artery stenoses.

AIM AND METHODS: The role of simultaneous transesophageal Doppler assessment of coronary flow reserve (CFR) in the left anterior descending artery (LAD) and coronary sinus (CS) in the diagnostics of hemodynamically significant LAD stenoses of various localization was studied in 16 CAD patients with angiographically proven >50% stenotic atherosclerosis of the LAD (nine--in the proximal third, seven--in the mid and/or distal third) and 23 healthy volunteers (all men). Dipyridamole was used as a stress agent. The diastolic phase of coronary flow in the LAD and the antegrade phase of coronary flow in the CS were analyzed. CFR in the LAD and CS was calculated in two ways: one--as ratio of peak hyperemic flow velocity to the peak baseline blood flow velocity (CFR by Vp); two--as ratio of volume hyperemic blood flow velocity to the volume baseline blood flow velocity (CFR by VBF). The level of the CFR <2 in both ways of calculation was diagnosed as reduced. RESULTS: It was found that in CAD patients with LAD proximal stenosis the values of CFR in the LAD were significantly lower than those in healthy individuals by both Vp (1.87 +/- 0.43 and 3.54 +/- 0.82; P<0.001) and VBF (1.79 +/- 0.77 and 3.85 +/- 1.25; P<0.01). In proximal stenosis CFR in the LAD by Vp was significantly lower than that in non-proximal stenosis (1.87 +/- 0.43 and 3.31 +/- 1.44; P<0.05). Sensitivity and specificity of CFR <2 in the LAD by Vp in the diagnostics of LAD proximal stenosis were 56% and 97%, respectively; and CFR <2 in the LAD by VBF--89% and 93%, respectively. In CAD patients with both proximal and non-proximal LAD stenoses CFR in the CS by Vp was significantly lower than that in healthy volunteers and was 1.74 +/- 0.53, 1.63 +/- 0.30 and 2.56 +/- 0.87; P<0.05, respectively. Sensitivity and specificity of CFR <2 in the CS by Vp in the diagnostics of hemodynamically significant LAD stenoses were 75% and 70%, respectively. The values of CFR in the CS by VBF in CAD patients and healthy volunteers did not differ significantly. CONCLUSIONS: Thus, simultaneous evaluation of CFR in the LAD and CS makes it possible to diagnose hemodynamically significant LAD stenoses and to differentiate between proximal and non-proximal impairments.     

Comparison of transesophageal coronary sinus and left anterior descending coronary artery doppler measurements for the assessment of coronary row reserve

Background: Currently used methods for assessment of coronary flow reserve are invasive and require extensive laboratory equipment. Recently, noninvasive assessment of coronary flow reserve by transesophageal Doppler evaluation of coronary sinus (CS) or left anterior descending coronary artery (LAD) flow has been proposed. Direct comparison between these two techniques is lacking. Methods: Doppler recordings of CS and LAD flow velocity were obtained before and after 0.6 mg/kg/5 min dipyridamole in 16 patients with significant stenosis of the LAD (Group A) and in 14 control patients (Group B). Flow recordings and all measurements were performed in a blinded manner. For assessment of coronary flow reserve, Doppler measurements after dipyridamole were divided by the respective baseline values. Results: Doppler studies of the CS and LAD were feasible in 30 of 30 (100%) and 23 of 30 (71%) patients, respectively. Analyzing the maximum flow velocities, coronary flow reserve in Groups A and B was 1.18 ± 0.28 and 1.68 ± 0.53 with CS recordings and 1.78 ± 0.83 and 2.51 ± 0.76 with LAD recordings, respectively. Analyzing the velocity time integrals, coronary flow reserve in Groups A and B was 1.53 ± 0.68 and 2.59 ± 0.74 with CS recordings and 1.77 ± 0.38 and 2.68 ± 0.93 with LAD recordings, respectively. Correlation between LAD and CS recordings was 0.69 (p<0.001), when coronary flow reserve was calculated from the velocity time integral and 0.68 (p<0.001) when the maximum flow velocities were used. Conclusion: Both transesophageal Doppler techniques might be useful for noninvasive assessment of coronary flow reserve.     

Noninvasive quantitative evaluation of the patency of internal mammary artery grafts to the left anterior descending coronary artery by transthoracic Doppler echocardiography

OBJECTIVES: Evaluation of left anterior descending coronary artery (LAD) flow by transthoracic Doppler echocardiography (TTDE) may allow assessment of anastomosis of the internal mammary artery (IMA) grafted to the LAD. This study tested the feasibility of TTDE to evaluate anastomotic stenosis of the IMA grafted to the LAD. METHODS: TTDE was performed in 66 patients (48 men and 18 women, mean age 67 +/- 10 years) with left or right IMA grafts to the LAD. The distal IMA flow at the anastomosis was visualized and the percentage stenosis was evaluated by the continuity equation using the anastomotic and pre-anastomotic flow velocity measured by TTDE as well as by angiography. If the anastomotic flow was not visualized by TTDE, the absence of augmented diastolic flow of the proximal IMA, by using the supraclavicular approach, with diastolic to systolic mean velocity ratio < 0.25 was considered as anastomotic occlusion. RESULTS: Anastomotic flow was visualized and the percentage stenosis was obtained by the continuity equation in 50 patients. In 4 of the remaining 16 patients, the proximal IMA flow by TTDE showed the occlusion pattern. In these 54 (82%) patients, the percentage stenosis by TTDE showed a significant correlation with that by angiography (r2 = 0.86, p < 0.0001). In all the remaining 12 patients with the patent proximal IMA pattern but without visualized anastomotic flow, the patency was confirmed by angiography. CONCLUSIONS: TTDE enables direct visualization and quantitative evaluation of the anastomotic patency in patients with IMA graft to the LAD.     

Outcomes of left internal mammary artery with saphenous vein composite graft to bypass the left anterior descending artery: a propensity-matched study

BackgroundThis study aimed to evaluate the early and mid-term outcomes of a novel strategy of using the in-situ left internal mammary artery (LIMA) with the great saphenous vein graft (SVG) to bypass the left anterior descending artery (LAD) in coronary artery bypass grafting (CABG).MethodsA total of 979 patients took part in this retrospective observational study; 83 patients were propensity-score matched to the LIMA + SVG group and 83 to the LIMA − LAD group. Early mortality, postoperative complications, mid-term major adverse cardiovascular and cerebrovascular events (MACCE) were compared among the two matched groups after the procedure.ResultsNo significant differences in early mortality and postoperative complications rates were detected between the two matched groups. For mid-term outcomes, the incidence of MACCE was slightly higher in the LIMA + SVG group, but there was no significant statistical difference (14.9% vs. 12.8%, hazard ratio =1.20, 95% CI, 0.24 to 7.95; P=0.70) between the matched groups. Computed tomography coronary artery angiography (CTCA) images showed a LIMA + SVG composite graft patency rate of 94% (32/34) 25 months after the procedure.ConclusionsUsing the in situ LIMA with SVG to revascularize LAD was associated with comparable early and mid-term outcomes. These findings may provide an alternative emergency strategy when in situ LIMA cannot bypass LAD. Further study needs to be conducted to test longer-term outcomes.     

Incremental benefit of three‐dimensional transthoracic echocardiography in the assessment of left atrial appendage aneurysm leading to severe extrinsic compression of a coronary artery

Left atrial appendage aneurysm (LAA AN) is a rare disease entity, which can be congenital or acquired in nature. We report an adult patient with LAA AN presenting with anginal chest pain in whom live/real time three‐dimensional transthoracic echocardiography (3DTTE) provided incremental value over the two‐dimensional (2D) technique in providing a more comprehensive assessment of the lesion. A literature review of the salient features of LAA AN is also provided in a tabular form.     

Isolated anomaly of the left anterior descending coronary artery

An isolated anomaly of the left anterior descending coronary artery arising from the right sinus of Valsalva is described. A review of the literature shows that isolated anomalies of this vessel are very rare. However, the inability to visualize this vessel from the left sinus of Valsalva warrants careful search of the right sinus.     

应用多普勒导丝技术研究内乳动脉与冠状动脉前降支血流动力学

目的 比较内乳动脉(IMA)与冠状动脉前降支(LAD)相关血流动力学参数。方法应用血管内多普勒导丝记录22例患者IMA和LAD的平均峰值流速(APV)、舒张收缩流速比(DSVR),造影测量血管直径(D),计算血流量(F)。结果IMA的APV和DSVR与LAD相比有明显差别[分别为(38±12)cm/s VS(23±7)cm/s,P<0.001;0.6±0.3VS 2.4±1.1,P<0.001)];IMA的D和F明显低于LAD[分别为(2.3±0.4)cm vs(3.2±1.1)cm,P<0.05;(90±12)ml/min vs(260±12)ml/min,P<0.001]。结论IMA收缩期供血为主,血流量小;而LAD舒张期供血为主,血流量大。     

乳内动脉在冠状动脉旁路移植术中的应用

为了探索国人应用乳内动脉做冠状动脉旁路移植术的近期临床效果,从94年10月至98年3月共60例冠心病人采用乳内动脉、桡动脉及大隐静脉做冠状动脉旁路移植术(CABG).大多数为三支病变及左主干病变.中低温及常温体外循环,经主动脉根部间断灌注冷血或温血停跳液心肌保护.强调在取乳内动脉时要格外小心,不要用器械钳夹乳内动脉,牵拉应轻柔.采用8-0 Prolene线做乳内动脉与前降支等做远端吻合.吻合完成后应将乳内蒂固定于心脏表面,减少吻合口张力.最后切开左上心包让乳内动脉走行平坦,无张力.平均搭桥支数为3.5根.术后死亡1例,死亡率1.7%.使用乳内动脉做CABC是安全有效的.59例病人心绞痛完全缓解,活动能力及生活质量明显提高.     

Assessment of left ventricular function in patients with isolated severe disease of the left anterior descending artery: Clinical,electrocardiographic, hemodynamic,and angiographic correlations

The purpose of this study was to define the spectrum of left ventriculographic (LV) abnormalities in 60 patients with isolated ≥90% diameter narrowing of the left anterior descending artery (LAD). The patients were divided into three groups: Group I (26 patients) had normal left ventricular (LV) function with ejection fraction (EF) of >60% and no akinetic-dyskinetic segment representing abnormal contracting segments (ACS) of the left ventricular wall; Group II (15 patients) had mild to moderate LV dysfunction with EF of 40–60% and an akinetic-dyskinetic segment of < 30% of the end diastolic perimeter (0–30%; mean, 11.6%) and Group III (19 patients) had severe LV dysfunction with EF <40%, or an akinetic-dyskinetic segment of ≥30 % (30–81%; mean, 41.5%) or both. The data obtained from the history, physical examination, electrocardiogram (ECG), chest x-ray studies, hemodynamic studies, left ventriculography, and coronary arteriography were entered and filed on a memory disc in an IBM 370-168 computer. Analysis of the results showed: (1) more severe LV dysfunction is associated with increased incidence of large hearts, gallops, decreased cardiac output, and occlusion of the LAD. (2) ECG evidence of infarction is also associated with higher incidence of the abnormalities of the indices of LV dysfunction. (3) LAD occlusion (versus stenosis) has a higher incidence of severe LV dysfunction and prior infarction. (4) The site of LAD disease did not predict the extent of left ventricular dysfunction. (5) Collaterals did not protect against severe LV dysfunction.     

Noninvasive coronary flow velocity reserve measurement in the posterior descending coronary artery for detecting coronary stenosis in the right coronary artery using contrast-enhanced transthoracic Doppler echocardiography

BACKGROUND: Coronary flow velocity reserve (CFVR) measurement by transthoracic Doppler echocardiography (TTDE) has been found to be useful for assessing left anterior descending coronary artery (LAD) stenosis. However, this method has been restricted only for the LAD. The purpose of this study was to detect severe right coronary artery (RCA) stenosis by CFVR measurement using contrast-enhanced TTDE. METHODS: In 60 consecutive patients with angina pectoris (mean (SD) age: 60 (11), 18 women), coronary flow velocities in the RCA were recorded in the postero-descending coronary artery by contrast-enhanced TTDE at rest and during hyperemia induced by intravenous infusion of adenosine triphosphate (140 mcg/ml/kg). CFVR was calculated as the ratio of hyperemic to basal peak and mean diastolic flow velocity. CFVR measurements by TTDE were compared with the results of coronary angiography performed within 1 week. RESULTS: Coronary flow velocity was successfully recorded in 49 (82%) of the 60 patients with contrast agent. CFVR (mean (SD)) was 1.4 (0.4) in patients with, and 2.6 (0.6) in patients without significant stenosis in the RCA (%diameter stenosis > 75%, P < 0.001). Using the cutoff value 2.0 for CFVR in the RCA, its sensitivity and specificity in detecting significant stenosis in the RCA were 88% and 91%, respectively. CONCLUSION: CFVR measurement in the postero-descending coronary artery by contrast enhanced TTDE is a new, noninvasive method to detect significant stenosis in the RCA.     

Origin and distribution anomalies of the left anterior descending artery in 70,850 adult patients: multicenter data collection.

OBJECTIVES: To present the clinical and angiographic properties of the left anterior descending artery anomalies. BACKGROUND: Coronary artery anomalies are discovered in less than 1% of angiography series. Since the number of angiographies and coronary bypass operations are increasing significantly every day, these anomalies are of clinical importance. However, data about left anterior descending artery anomalies in literature is still scarce. METHODS: We reviewed the records of 70,850 patients who had undergone coronary angiographies at 4 different cardiology center from 1999 to 2005 years. RESULTS: Major congenital coronary anomalies were discovered in 171 of these cases (0,24%). The mean age of these patients was 61 +/- 11 (18-84) years. Ninety nine patients (58%) were male. Left anterior descending artery was involved in 12 patients (0.017%). In nine patients with the anomalous LAD there were concomittant congenital coronary artery anomalies. Concurrent coronary artery anomalies encountered were double left anterior descending artery type 4 (2 cases), double left anterior descending artery type 4 with double right coronary artery (1), double right coronary artery (1), double circumflex artery with anomalous left anterior descending artery (1), circumflex artery from right sinus of Valsalva (1), separate septal perforator and myocardial bridging of posterior descending artery (1), intercoronary communication, and ostial atresia of the left anterior descending artery and anomalous circumflex artery (1). CONCLUSION: Our series is the biggest series where relatively sufficient clinical and angiographic information about the LAD anomalies were provided.     

Noninvasive assessment of significant right coronary artery stenosis based on coronary flow velocity reserve in the right coronary artery by transthoracic Doppler echocardiography

BACKGROUND: Coronary flow velocity reserve (CFVR) measured by transthoracic Doppler echocardiography (TTDE) has been reported to be useful for the noninvasive assessment of coronary stenosis in the left anterior descending artery. However, the measurement of CFVR in the right coronary artery by TTDE has not yet been validated in a clinical study. OBJECTIVE: The aim of this study was to evaluate whether CFVR by TTDE can detect significant stenosis in the right coronary artery. METHODS: We studied 50 patients who underwent coronary angiography. Coronary flow velocity in the posterior descending branch of the right coronary artery (PD) was measured by TTDE both at baseline and during hyperemia induced by the intravenous infusion of adenosine triphosphate. CFVR was calculated as the hyperemia/baseline (average diastolic peak velocity). RESULTS: Adequate spectral Doppler recordings in the PD were obtained in 36 patients including 26 patients who were given an echocardiographic contrast agent to improve Doppler spectral signals. The study population was divided into 2 groups with (Group A;n = 11) and without (Group B;n = 25) significant stenosis in the right coronary artery. CFVR in Group A was significantly smaller than that in Group B (1.6+/-0.3versus2.5+/-0.4; P < 0.0001). The sensitivity of a CFVR of <2.0 for predicting the presence of significant stenosis in the right coronary artery was 91%, and the specificity was 88%. CONCLUSIONS: The measurement of CFVR in the PD by TTDE is useful for the noninvasive assessment of significant stenosis in the right coronary artery.     

Giant left atrial appendage aneurysm compressing the left anterior descending coronary artery

Left atrial appendage aneurysm (LAAA) is a rare congenital structural heart disease. It is often diagnosed by echocardiography; however, other imaging modalities can add to its diagnosis and its potential effects on the surrounding structures. A 16‐year‐old boy presented with dyspnea and palpitation. Transthoracic echocardiography showed a large LAAA communicating with the LA through a narrow neck with impaired left ventricular (LV) systolic function. Multidetector cardiac tomography showed that the LAAA is compressing the left anterior descending artery. The LAAA was surgically resected followed by improvement of the LV systolic function.     

Improving feasibility of posterior descending coronary artery flow recording by transthoracic Doppler echocardiography.

AIMS: Recording coronary arteries' flow by transthoracic Doppler echocardiography (TTDE) is a new task. Despite several studies concerning the left anterior descending artery (LAD) exist, the same for posterior descending coronary artery (PD) do not. Reported feasibility is not more than 76%. The aim of the study was to try to improve feasibility by using an additional two-dimensional view as a guide. METHODS AND RESULTS: PD flow recording was performed in 35 consecutive unselected patients under the guidance of the usual two-dimensional modified view [a two-chamber view (2-C)], and with a new four-chamber modified view (4-C). A semi-quantitative growing-quality score (from 0 to 3 points) to the trace was given. Contrast enhancement was used if PD was not visualized without it. The overall feasibility was 80%. A good or very good velocity signal (TTDE score > or = 2) was observed in 48% of patients without contrast enhancement. Time for first visualization of PD was short and significantly lower in 2-C than in 4-C (66 +/- 39 vs 90 +/- 70 s, respectively, P<0.05). CONCLUSIONS: TTDE recording of PD flow gained better feasibility being guided by two views. Maximal time for first visualization of PD was less than 3 min.     

Whole-heart coronary magnetic resonance angiography of double left anterior descending artery

Double left anterior descending artery arising from the left and right coronary arteries is an extremely rare congenital coronary anomaly. We describe, for the first time, three-dimensional, whole-heart coronary magnetic resonance angiographic findings of double left anterior descending artery.