Acute coronary syndrome due to extrinsic compression of the left main coronary artery in a patient with severe pulmonary hypertension: successful treatment with percutaneous coronary intervention

A patient with severe pulmonary (arterial) hypertension (PH) presented with a non-ST segment elevation myocardial infarction and recurrent angina at rest. Coronary angiography showed severe ostial left main coronary artery (LMCA) stenosis; coronary arteries were otherwise normal. Intravascular ultrasonography (IVUS) showed deformation of the LMCA due to extrinsic compression from a markedly dilated main pulmonary artery, which was confirmed by cardiac computed tomography. The LMCA was successfully stented using a paclitaxel-eluting stent resulting in complete resolution of angina. Extrinsic compression of the LMCA should be considered in patients with severe PH and angina; IVUS may aid in the diagnosis. Percutaneous stent implantation may be the preferred treatment in this high-risk group of patients.     

Chest pain in a patient with pulmonary arterial hypertension

Chest pain is a frequent symptom in patients with pulmonary arterial hypertension (PAH). Left main coronary artery (LMCA) extrinsic compression from a pulmonary artery (PA) is an increasingly recognized cause of angina or complications, such as acute myocardial infarction, left ventricular dysfunction, arrythmia, and sudden death.We report the case of a 45-year-old patient with pre-capillary pulmonary hypertension (PH), a patent ductus arteriosus corrected surgically during adolescence, and chronic constrictive bronchiolitis. In 2016, the patient began to report oppressive chest pain and worsening fatigue. Computed tomography coronary angiography (CTCA) showed extrinsic LMCA compression by a dilated PA, which was confirmed by invasive coronary angiography and intravascular ultrasound. After stent implantation, the patient reported symptom resolution, and has been asymptomatic ever since.Imaging studies, in particular CTCA, play an important role in the diagnosis of LMCA compression in patients with PAH. The reported case supports the efficacy and safety of stent implantation as a therapeutic option, as already demonstrated in the literature. It shows the complexity of decision making on the operability of systemic-to-pulmonary shunts and reinforces the importance of continuous diagnostic testing.     

Stenting of a left main coronary artery compressed by a dilated main pulmonary artery

Left main coronary artery (LMCA) disease caused by external compression by a dilated main pulmonary artery (MPA) is an uncommon clinical entity but is one of the reversible causes of chest pain in patients with pulmonary hypertension. Traditionally, treatment of LMCA disease involves coronary artery bypass graft surgery. However, for LMCA compression by a dilated MPA, coronary angioplasty with stenting has recently been reported to have good outcomes and might be more suitable in some patients with high risk associated with surgery. Herein, we describe a 54‐year‐old man with pulmonary arterial hypertension and external compression of the LMCA by the dilated main pulmonary artery that was treated with angiographic and intravascular ultrasound‐guided coronary angioplasty and stenting. Also we briefly review current literatures about LMCA compression by a dilated MPA. © 2013 Wiley Periodicals, Inc.     

Left main coronary artery compression in pulmonary hypertension

Extrinsic compression of the left main coronary artery (LMCA) by a dilated pulmonary artery (PA) in the setting of pulmonary arterial hypertension (PAH) is an increasingly recognized disease entity. LMCA compression has been associated with angina, arrhythmia, heart failure, and sudden cardiac death in patients with PAH. Recent studies suggest that at least 6% of patients with PAH have significant LMCA compression. Screening for LMCA compression can be achieved with computed coronary tomography angiography, with a particular emphasis on assessment of PA size and any associated downward displacement and reduced takeoff angle of the LMCA. Indeed, evidence of a dilated PA (>40 mm), a reduced LMCA takeoff angle (<60° ), and/or LMCA stenosis on CCTA imaging should prompt further diagnostic evaluation. Coronary angiography in conjunction with intravascular imaging has proven effective in diagnosing LMCA compression and guiding subsequent treatment. While optimal medical therapy and surgical correction remain in the clinician's arsenal, percutaneous coronary intervention has emerged as an effective treatment for LMCA compression. Given the prevalence of LMCA compression, its associated morbidity, and mortality, and the wide array of successful treatment strategies, maintaining a high degree of suspicion for this condition, and understanding the potential treatment strategies is critical.     

Percutaneous intervention of left main coronary artery compression by pulmonary artery aneurysm

Background: Extrinsic compression of the left main coronary artery (LMCA) by a pulmonary artery aneurysm (PAA) has become increasingly recognized as an etiology of angina in patients with pulmonary arterial hypertension (PAH). The purpose of this study was to assess the feasibility and efficacy of LMCA stenting in the treatment LMCA stenosis because of PAA. Methods: Retrospective analysis of data on patients with PAH who presented with angina and underwent percutaneous intervention of their LMCA compression because of PAA was performed. Results: Five patients (age 51 ± 16 years, all female) with PAH presented with angina and underwent LMCA stenting between 2007 and 2009. Four had positive cardiac enzymes. LMCA compression because of a PAA was diagnosed in all patients with cardiac CT angiography after echocardiography demonstrated an enlarged pulmonary artery. LMCA stenting was successfully performed in all patients with resolution of angina and electrocardiographic abnormalities. After a mean follow‐up of 16.6 ± 15.7 months (range of 5–39 months), patients remained angina free, no complications of the procedure were noted, and long term stent patency was confirmed in three of the five patients who underwent repeat cardiac CT angiography. Conclusions: LMCA stenting appears to be a feasible and durable option in patients who present with angina because of compression by PAA. This procedure was well tolerated and is of particular value given the increased surgical risk in patients with PAH. © 2010 Wiley‐Liss, Inc.     

Left main coronary artery compression from right pulmonary artery stenting

Complications related to pulmonary artery stenting include stent migration, jailing of vessels, vessel rupture, and compression of surrounding structures. Compression of the left main coronary artery (LMCA) as a result of stent placement in the right pulmonary artery (RPA) is extremely rare. We present two patients post repair of congenital heart disease who suffered LMCA compression following RPA stenting. The first patient experienced acute coronary insufficiency in the cardiac catheterization laboratory, whereas the second patient had a more chronic course. We also present a third patient who had a CT angiogram that demonstrated a close spatial relationship between the RPA and the LMCA. Based on our previous experiences, we felt that this patient was at significant risk for LMCA compression if the RPA were stented. Coronary compression is rare complication of pulmonary artery stenting but should be considered in cases with history of repaired congenital heart disease. © 2009 Wiley‐Liss, Inc.     

Left main coronary artery and aortic root compression associated with atrial septal defect and pulmonary hypertension

The extrinsic compression of left main coronary artery (LMCA) by dilated pulmonary artery is rarely reported. Various congenital and acquired diseases were shown to cause extrinsic LMCA compression. Here we present a child with aortic root and LMCA compression due to dilated pulmonary trunk and causing angina like chest pain. The patient had also electrocardiographic evidence of myocardial ischemia. This case report will be a guide for the evaluation and surgical treatment of the patients with pulmonary hypertension and LMCA compression.     

Extrinsic compression of left main coronary artery due to dilated pulmonary trunk resulting in ischaemic symptoms

Left coronary artery compression syndrome is an uncommon entity and characterized by compression of the LMCA in-between the aorta and an enlarged main pulmonary arterial trunk. It is usually associated with a congenital cardiac defect. Cardiac 64-slice MDCT provides a non-invasive and an accurate method for assessing the degree of dynamic LMCA compression throughout the cardiac cycle, its angulation relative to the left sinus of Valsalva and depiction of pulmonary pathology, making it a valuable tool in the workup of patients suspected of left coronary artery compression.     

Non-invasive evaluation of systolic pressure of the pulmonary artery in patients with tricuspid regurgitation, using Doppler echocardiography

STUDY OBJECTIVE: To quantify the systolic pulmonary artery pressure (SPAP) by continuous wave Doppler echocardiography and record the prevalence of tricuspid regurgitation (TR). DESIGN: Prospective analysis of 42 patients (pts), submitted to right heart catheterization (RHC). SETTING: Pts referred to the Echocardiographic Laboratory at Sta. Marta Hospital - H.C.L. PATIENTS: Sequential sample of 42 pts with several cardiac pathologies, subjected to RHC and 2D Doppler Echocardiography. INTERVENTIONS: The right ventricular and SPAP were recorded in the hemodynamic exam. We considered pulmonary hypertension (PH) if SPAP was greater than 35 mmHg or mean pressure greater than 20 mmHg. The pts were divided into two groups: I-pts without PH and II-pts with PH. The 2D Doppler echocardiography was made within 24 H of the hemodynamic one. Peak gradient (pg) of TR and the correlation with catheterization data were analysed. RESULTS: Hemodynamic--The mean SPAP in the sample was 46 +/- 21.5 mmHg (27 +/- 4.6 in group I and 55 +/- 20.2 mmHg in II). In 35 pts with TR the mean SPAP was 50.3 +/- 21.2 mmHg. Doppler--The pressure gradient was 40 +/- 18.7 mmHg. 57% pts of the group I and 96% II had TR p less than 0.001. The correlation between Doppler gradient and SPAP was r = 0.95, and no change was noted when 7 is used as a constant. CONCLUSION: Continuous wave Doppler echocardiography is a non invasive technic useful to the quantitative analysis of SPAP.     

Precapillary pulmonary hypertension: effect of Captopril

The immediate and sustained haemodynamic effects of Captopril (CPT), an oral inhibitor of angiotensin converting enzyme, were studied in six patients (pts) with severe pulmonary hypertension (PH) (pulmonary artery pressure: mean +/- SD value = 57 +/- 20 mmHg). Two pts had primary PH, 2 embolic PH and 2 Eisenmenger Physiology (EP). Administration of 100 mg of CPT in a single oral dose produced a significant decrease only in systemic arterial pressure (SAP) (p less than 0.025) and systemic vascular resistance (SVR) (p less than 0.05) in 5 of 6 pts. Heart rate (HR), cardiac index (CI), pulmonary vascular resistance (PVR), pulmonary arterial (PAP), pulmonary wedge (PWP) and right atrial pressure (RAP) did not change significantly. These results were confirmed in a repeat haemodynamic study after 4 months of long-term treatment with 50 or 100 mg of CPT 3 times daily. In 1 pt with EP and severe congestive heart failure (CHF) the same chronic treatment produced a marked decrease in HR (from 114 to 88 b/min), RAP (from 10 to 1 mmHg), PWP (from 15 to 6 mmHg), PVR (from 41 to 30 UR), SVR (from 58 to 43 UR). Systemic CI increased from 1.68 to 2.60 l/min/m2 and pulmonary CI from 1.64 to 2.5 l/min/m2; no changes were seen in PAP and SAP. These data suggest that CPT is not effective on pulmonary haemodynamics in pts with precapillary PH and normal CI whereas the drug seems to influence favourably the pulmonary circulation in pts with PH secondary to or associated with left ventricular failure. The necessity of evaluating not only PVR but PAP as well, in studying the effect of vasodilators especially in pts with precapillary PH and normal CI, is discussed. In fact a reduction of PAR without decrease of PAP, as frequently seen in previous reports, is probably due to a primary increase of CI induced by the drug.     

Effect of primary angioplasty on total or subtotal left main occlusion: analysis of incidence, clinical features, outcomes, and prognostic determinants

BACKGROUND: Although acute left main coronary artery (LMCA) occlusion is a rare clinical entity, it carries a very high mortality rate. The purposes of this study were to evaluate the effect of primary angioplasty for a severely obstructed or totally occluded LMCA, and to determine the incidence, clinical features, outcome, and prognostic determinants in this clinical setting. MATERIALS AND METHODS: Between May 1993 and July 2000, a total of 740 patients with acute myocardial infarction underwent primary angioplasty in our hospital. Eighteen of 740 patients (2.4%) with a severely obstructed or totally occluded LMCA constituted the population of this study. RESULTS: Seventeen of 18 patients (94.4%) experienced pulmonary edema (including 14 patients in cardiogenic shock). Six patients (33.3%) sustained sudden death due to malignant ventricular tachyarrhythmias. Coronary angiography showed that there were variable grade flow of intercoronary collaterals in 12 patients (66.7%), a totally occluded LMCA in 8 patients (44.4%), an incompletely occluded LMCA in 10 patients (55.6%), and a dominant right coronary artery (RCA) in 16 patients (88.9%). Primary angioplasty of the LMCA was performed with a 72.2% procedural success rate. Four patients (22.2%) received coronary artery bypass surgery after angioplasty. Six patients (33.3%) died in the hospital. Two patients died after discharge. Ten of 18 patients (55.6%) survived in long-term follow-up (mean +/- SD, 44 +/- 14 months). Those patients who survived to be discharged had significantly higher combined coexisting incidence of intercoronary collaterals, dominant RCA, and incompletely occluded LMCA (100% vs 0.0%, p = 0.0006) than those patients who died in the hospital. CONCLUSIONS: Acute obstructive LMCA disease generally presented as pulmonary edema, cardiogenic shock, or sudden death. Only those who had combined coexistence of intercoronary collaterals, a dominant RCA, and an incompletely occluded LMCA could survive to be discharged. Our experience suggests that primary LMCA angioplasty is a feasible and effective procedure, and it may save lives in this clinical setting.     

568例急诊冠状动脉造影的临床体会

目的评价对急性冠状动脉综合征患者施行急诊冠状动脉造影的安全性与有效性。方法自1996年1月至1999年12月,我们共施行急诊冠状动脉造影568例,其中疑诊急性心肌梗死416例,疑诊不稳定性心绞痛152例。结果416例拟诊急性心肌梗死病例中,有328例施行了梗死相关血管的直接经皮冠状动脉腔内成形术(PrimaryPTCA,P-PTCA)治疗;有32例造影发现冠状动脉梗死相关血管直径狭窄<75%,前向血流TIMIⅢ级,未行P-PTCA治疗;有12例左主干和(或)三支血管病变患者施行急诊冠状动脉旁路移植术（CABG）;16例左主干和(或)三支血管病变患者在主动脉内球囊反搏(IABP)辅助下,行择期CABG治疗;有8例因梗死相关血管不能确定或是不适宜P-PTCA或CABG病例接受了冠状动脉内溶栓治疗,有4例梗死相关血管细小,未行特别处理;有13例急诊冠状动脉造影示结果正常或体表心电图判定的梗死相关血管正常。152例拟诊不稳定性心绞痛患者中行急诊PTCA治疗108例,CABG33例,动脉造影正常8例,因弥漫性冠状动脉病变不适宜PTCA/CABG治疗,选用IABP短期辅助治疗加药物治疗维持2例。2例急性心梗和1例梗死后心绞痛患者死于术中或术后即刻。结论对于急性冠状动脉综合征患者施行急诊冠状动脉造影是必要的和安全可行的。     

Extrinsic compression of the left main coronary artery by a dilated pulmonary artery: clinical, angiographic, and hemodynamic determinants.

Extrinsic compression of the left main coronary artery (LMC) by the pulmonary artery (PA) is a very unusual and poorly understood entity, usually associated with the presence of adult congenital heart disease. We identified 12 patients (age range, 6 months to 55 years) with LMC stenosis (> or = 50%) presumably secondary to compression by a dilated main PA and related to various forms of heart disease (11 congenital, 1 pulmonary hypertension). In all cases, the main PA was dilated with the main PA/aortic root diameter increased (mean, 2.0; normal value, < or = 1.0), and in all but two, PA pressures were increased (> 30 mm Hg systolic). Left coronary trunk stenosis was usually visualized in only one angiographic view (best seen in 45 degrees left anterior oblique, 30 degrees cranial projection). The LMC also appeared to be inferiorly displaced and in close contact with the left aortic sinus (mean angle between sinus and LMC was 23 degrees +/- 13 degrees, a control group was 70 degrees +/- 15 degrees ). In one patient, surgical correction of the dilated PA was associated with a reduction in LMC stenosis from 85% to < 50% and less inferior left main displacement (from 25 degrees to 50 degrees ). Patients with a dilated main PA may exhibit extrinsic LMC compression leading to significant eccentric narrowing and downward displacement of the LMC. In the presence of significant dilatation of the main PA from any etiology, functional and/or anatomic studies should be performed to exclude significant LM obstruction.     

Extrinsic Compression of the Left Coronary Ostium by the Pulmonary Trunk: Management in a Case of Eisenmenger Syndrome

Extrinsic compression of the left main coronary artery by a massively dilated pulmonary artery in patients who have severe pulmonary hypertension can lead to significant myocardial ischemia. A 58-year-old man with a large patent ductus arteriosus and Eisenmenger syndrome presented with angina at rest and worsening heart failure of 3 months'' duration. The new symptoms were recognized to be secondary to extrinsic compression of the left main coronary artery ostium by a dilated main pulmonary artery and were successfully relieved by the placement of a metallic stent in the affected segment of the left main coronary artery. Multislice computed tomographic imaging after 6 months showed stent patency and the intimate relation of the stented vessel to the dilated main pulmonary trunk. We discuss diagnostic and management issues pertaining to this uncommon clinical entity.Key words: Angina pectoris/etiology, angioplasty, transluminal, percutaneous coronary, constriction, patho-logic/etiology, coronary stenosis/etiology, dilatation, pathologic/complications, ductus arteriosus, patent, Eisenmenger complex/ complications, hypertension, pulmonary/complications, stents, tomography, X-ray computedA pulmonary trunk dilated by severe pulmonary artery hypertension (PAH) can compress the aortic ostium of the left main coronary artery (LMCA).¹ If the primary disease process causing PAH cannot be reversed, progressive coronary narrowing can lead to left ventricular myocardial dysfunction, angina, and worsening of heart failure.² We report the case of a 58-year-old patient with a large patent ductus arteriosus and Eisenmenger syndrome who presented with angina at rest and worsening of heart failure due to left ventricular dysfunction. Coronary angiography showed extrinsic compression of the LMCA, at its origin, by a dilated pulmonary trunk. Stenting of the LMCA resulted in immediate relief of angina and led to symptomatic improvement.     

Favorable Long-Term Survival in Patients Undergoing Stent PCI of Unprotected Left Main Coronary Artery Compared to Predicted Short-Term Prognosis of CABG Estimated by EuroSCORE: Clinical Determinants of Long-Term Outcome

Aims/Methods: The long-term outcome of patients (pts) undergoing percutaneous coronary intervention (PCI) of unprotected left main coronary artery (LMCA) is unclear so far . We prospectively investigated the outcome of 102 consecutive patients who underwent stent PCI of unprotected LMCA. Patients were divided according to clinical indication for PCI: stable coronary artery disease (CAD) (N = 60), NSTEMI (N = 18), STEMI (N = 24). Expected in-hospital mortality of coronary artery bypass grafting (CABG) was calculated using the European System for Cardiac Operative Risk Evaluation ( EuroSCORE ) and compared to the observed survival rate during long-term follow-up (mean 1.8 ± 1.2 years).
Results: The observed 30-day mortality was 1.7% (1/60 pts) in patients with stable CAD, 11% (2/18 pts) in NSTEMI patients, and 13% (3/24 pts) in STEMI patients. The observed mortality was lower than the predicted mortality of CABG as calculated by the logistic EuroSCORE. Using receiver-operator characteristics curves (ROC), EuroSCORE demonstrated a high predictive value for both 30-day mortality as well as 1-year mortality (AUC > 0.8; P < 0.01). Prognostically relevant patient related factors (P < 0.01) included severely reduced left ventricular ejection fraction (HR 3.24), ACS (HR 3.18), STEMI (HR: 3.01), Killip class IV (HR 7.69), occurrence of neoplastic disease (HR 3.97), and elevated CRP (HR 3.86).
Conclusions: LMCA-PCI was associated with lower long-term mortality rates compared to the estimated mortality of CABG. This prospective observational study suggests that DES-PCI of unprotected LMCA in "all-comers" can be carried out with reasonable risk .     

Vascular remodeling in experimentally induced subacute canine pulmonary hypertension

We quantified in vivo pulmonary vascular remodeling in a large animal model of pulmonary hypertension (PH). In group PH (n = 6), 3 mg/kg dehydromonocrotaline (DHMC) was administered to 12-week-old beagles via a right atrial injection. Eight weeks after DHMC in group PH, pulmonary artery pressure increased significantly (P < .05) from 18 +/- 2 mm Hg at baseline to 30 +/- 4 mm Hg. Medial wall thickness and medial wall area as a percentage of total vessel diameter or area was significantly higher (P < .05) in group PH (29 +/- 9% and 48 +/- 12%) than in a control group (n = 5) (7 +/- 1% and 14 +/- 1%). Neointimal proliferation was observed in 42% of pulmonary arterioles in the PH group but never in the control group. We conclude that a single injection of DHMC in young beagles, in addition to the development of moderate degrees of PH after 8 weeks, causes significant pulmonary vascular remodeling, with features similar to those observed in patients with primary PH.     

Comparison of ejection fraction and pulmonary blood volume ratio as markers of left ventricular function change after coronary angioplasty

Exercise-induced increases in pulmonary blood volume ratio have been shown to be a sensitive marker of coronary artery disease, and correlate well with exercise-induced increases in left ventricular filling pressure. To compare the impact of single vessel coronary disease on left ventricular systolic function (ejection fraction) versus diastolic filling pressure (pulmonary blood volume) before and after intervention, serial supine exercise gated blood pool scans were performed before and after coronary angioplasty in 32 patients with isolated left anterior descending coronary artery disease. By applying previously established criteria of abnormal ejection fraction (rest less than 50% or failure to rise by 5% with exercise) and pulmonary blood volume ratio (greater than 1.06), 66% of the patients were found to have abnormal responses before angioplasty by ejection fraction compared with 81% abnormal responses by pulmonary blood volume ratio (p = 0.15). After angioplasty, the proportion of patients with abnormal ejection fraction (59%) was essentially unchanged, whereas only 38% continued to have an abnormal pulmonary blood volume ratio (p less than 0.01 compared with before angioplasty). The mean pulmonary blood volume ratio also decreased significantly from 1.15 +/- 0.10 before angioplasty to 1.02 +/- 0.15 after angioplasty (p less than 0.001). It is concluded that in single vessel coronary artery disease: 1) pulmonary blood volume ratio is abnormal at least as frequently as is ejection fraction; 2) in contrast to ejection fraction, pulmonary blood volume ratio improves significantly after successful angioplasty; and 3) pulmonary blood volume ratio may be a more sensitive indicator of changes in ventricular function after an intervention in single vessel coronary disease.     

Left main coronary artery extrinsic compression syndrome: a combined intravascular ultrasound and pressure wire

The compression of the left main coronary artery (LMCA) secondary to pulmonary artery trunk dilatation is a relatively new entity that has been associated with severe pulmonary hypertension. It is associated with acyanogen congenital cardiopathies or idiopathic pulmonary arterial hypertension. The natural history is unknown and its treatment has been based more on the severity of the angiographic compression than on the objective demonstration of myocardial ischemia. We report a case of a woman with severe pulmonary arterial hypertension due to an atrial septal defect with extrinsic compression of the LMCA and a physiopathologic approach to guide its treatment.     

The serotonin pathway in pulmonary hypertension

The nature of the primary defect responsible for triggering and maintaining pulmonary artery smooth muscle (PA-SMC) proliferation in pulmonary artery hypertension (PH) is poorly understood but may be either an inherent characteristic of PA-SMCs or a secondary response to an external abnormality, such as up-regulation of growth factors. In previous studies, we found that cultured PA-SMCs from patients with idiopathic PH (iPH) had an abnormally strong proliferative response to serotonin or serum (which contains high levels of serotonin). This abnormal response is due to overexpression of the serotonin transporter (5-HTT) which mediates the mitogenic action of serotonin. That 5-HTT plays a key role in pulmonary vascular remodeling is supported by experimental studies showing that transgenic animals overexpressing 5-HTT in smooth muscle (at a level close to that seen in PH) spontaneously develop pulmonary vascular remodeling and PH. Conversely, mice with targeted S-HTT gene disruption are protected against hypoxic PH, and selective 5-HTT inhibitors reverse or prevent experimental PH. In patients with chronic lung disease, a close association has been found between a 5-HTT gene polymorphism and the severity of pulmonary hypertension. Agents capable of selectively inhibiting 5-HTT-mediated PA-SMC proliferation deserve to be investigated as potential treatments for pulmonary hypertension.