Left main coronary artery and right pulmonary vein compression by a large pulmonary artery aneurysm

Extrinsic compression of coronary and pulmonary vasculature

Coronary artery disease from atherosclerosis induced stenosis remains the leading cause of acute coronary syndrome (ACS) and death worldwide, however extrinsic compression of coronary arteries from adjacent anatomical and pathological structures is an infrequent but important diagnosis to be aware of, especially given the nonspecific symptoms of chest pain that mimic angina in patients with pulmonary hypertension (PHT) and congenital heart disease. Non-invasive CT angiography is an invaluable diagnostic tool for detection of coronary artery compression, pulmonary artery dilatation and pulmonary vascular compression. Although established guidelines are not available for management of left main coronary artery (LMCA) compression syndrome, percutaneous coronary intervention and stent implantation remain a feasible option for the treatment, specifically for patients with a high surgical risk. Treatment of pulmonary vein or artery compression is more varied and determined by etiology. This review article is focused on detailed discussion of extrinsic compression of coronary arteries, mainly the LMCA and brief discussion on pulmonary vasculature compression by surrounding anatomical and pathological entities, with focus on pathophysiology, clinical features, complications and role of imaging in its diagnosis and management.

Left Main Coronary Artery Stenting to Relieve Extrinsic Compression by a Giant Pulmonary Artery Aneurysm in a Patient with Idiopathic Pulmonary Artery Hypertension

Pulmonary artery aneurysm (PAA) is a rare but lethal disease. We present a female patient with idiopathic pulmonary artery hypertension (IPAH)-related PAA, who suffered from unstable angina pectoris. Multi-detector computed tomography and coronary angiogram revealed extrinsic compression of the left main coronary artery (LMCA) caused by a giant PAA with severe ostial stenosis. Intravascular ultrasound showed an oval-shaped ostium of the LMCA, indicating extrinsic compression. After successful LMCA stent implantation, chest pain was greatly relieved. This case illustrates that beyond right ventricle ischaemia and coronary atherosclerotic disease, LMCA compression by PAA should be considered in the differential diagnosis of angina in patients with IPAH related PAA. In addition, intravascular ultrasound can be used to confirm the diagnosis and guide the stent implantation safely.

Giant high-pressure pulmonary artery aneurysm in an elderly patient with chronic obstructive pulmonary disease

The authors report the case of a 74-year-old man, with a history of chronic obstructive pulmonary disease (COPD), GOLD grade 3, stable for the past two decades, who was admitted to our center with severe right heart failure. The chest radiograph showed moderate heart enlargement mainly of the right atrium and pulmonary artery, similar to previous chest radiographs in the previous 20 years. The transthoracic echocardiogram showed a pulmonary artery aneurysm (PAA), dilatation of the right chambers with pulmonary artery systolic pressure of 52 mmHg, and preserved right ventricular systolic function. A thoracic computed tomography scan confirmed the presence of a giant PAA 72 mm in diameter. The patient was started on high-dose diuretics, with significant clinical improvement. After optimization of medical therapy right heart catheterization was carried out with the patient in optimal clinical condition, which revealed mild precapillary pulmonary hypertension with a mean pulmonary artery pressure of 26 mmHg. On the basis of the clinical and imaging findings a stable, giant, high-pressure, PAA was diagnosed secondary to pulmonary hypertension induced by COPD, with a 20-year follow-up without need for surgical repair, which helped in our decision to maintain medical surveillance. The recent onset of heart failure is explained by the unfavorable evolution of COPD. This case may change the attitude expressed in previous studies favoring the choice of an invasive approach to treat giant high-pressure PAAs, instead supporting the maintenance of medical treatment.

[Giant pulmonary artery aneurysm: etiology and an exceptional 17 years natural course]

True pulmonary artery aneurysm (AAP) is rare and represent less than 1% of intra-thoracic aneurysms. We report a case of a AAP in a patient with a likely cor triatrium sinister, with an obstructive membrane responsible for pulmonary hypertension, explaining AAP. The long-term evolution of 17 years is made to an uncomplicated myocardial infarction. The patient died eight months later suddenly probably due to the rupture of the PAA.

[Aneurysmal dilatation of pulmonary artery and its branches on mitral stenosis: a case report]

Pulmonary arteries aneurysms are rare and the rarely described bilateral aneurysms. A 45-year-old patient carrier of mitral stenosis was admitted for dyspnoea class III of the NYHA, chest pain and a not infectious cough. The clinical examination found semiology of mitral stenosis, tricuspid incapacity and pulmonary arterial hypertension. The electrocardiogram showed atrial fibrillation and right ventricle hypertrophy. Chest X-ray found a cardiomegaly, an aspect of double outline of the inferior right bow, a prominent aspect of the left average bow reminding an aneurysm of the left pulmonary artery. The echocardiography Doppler found a pure tight mitral stenosis (mitral surface=0.6 cm(2)), a dilation of the trunk of the pulmonary artery (diameter=74 mm) and of its branches (diameter of the right pulmonary artery=28 mm, diameter of the left pulmonary artery=36 mm) seat of a spontaneous contrast. The left atrium and right cardiac cavities were also dilated. There was an important tricuspid incapacity with a major pulmonary hypertension (systolic pulmonary arterial=109 mmHg). The thoracic angioscan showed a pseudoaneurysm of the trunk of pulmonary artery and its branches to their distal parts. Under diuretic, anticoagulating and analgesic treatment the clinical signs improved however the spontaneous contrast persisted. The patient was rejected by the surgery for exceeded clinical board. She is at present followed in our service for 5 months.

Prone position is essential for detection of pulmonary vein pseudostenosis by enhanced multidetector computed tomography in patients who undergo pulmonary vein isolation

BACKGROUND

Pulmonary vein (PV) stenosis is a major complication of PV isolation (PVI) by catheter ablation, so in the present study the optimal position for detecting PV stenosis on enhanced multidetector computed tomography (MDCT) image acquisition was determined.

METHODS AND RESULTS

The 64-slice enhanced MDCT was carried out before and after PVI in 116 consecutive patients with atrial fibrillation while they were in the prone position, as well as while supine. The supine position MDCT image showed >50% diameter stenosis of the PV in 11 (9%) patients before PVI (% diameter stenosis: mean 55+/-4%, range 51-65%). Greater than 50% diameter stenosis was seen in the left inferior PV in all 11 patients. The prone position attenuated the PV stenosis findings in the MDCT images in all 11 patients (mean 9+/-6%, range 2-18%). Stenosis visualized on images acquired in the supine position was, therefore, concluded to be pseudostenosis caused by descending aorta compression. At 3 months after PVI, no significant changes in PV diameter were observed in these 11 patients.

CONCLUSION

The present study demonstrated that the prone position is essential for eliminating PV pseudostenosis observed on supine-position enhanced MDCT images. The results also indicate that preexisting PV organic stenosis is rare.

Differential diagnosis of non-atherosclerotic left main coronary artery stenosis

A left main coronary artery (LMCA) stenosis without any atherosclerotic changes elsewhere in the coronary artery tree is a rare finding, and some uncommon reasons for luminal narrowing should be considered. An unusual case of non-atherosclerotic LMCA stenosis is reported.A middle-aged patient presented with acute myocardial infarction. An immediate coronary angiography was ordered and revealed a subtotal mid LMCA stenosis. A drug-eluting stent was successfully implanted in the LMCA.Operative revascularisation was recommended. Routine surgery was performed and surprisingly revealed an extended mass of a mediastinal tumour surrounding the aortic root. Histopathological examination of the tumour revealed a poorly differentiated squamous cell carcinoma.Postoperatively, the patient was treated with chemotherapy (carboplatin and docetaxel). Five years after the first admission to our hospital, the patient died as a result of ventricular fibrillation.The differential diagnosis of non-atherosclerotic LMCA stenoses is discussed.

Compression of the left atrium by the thoracic aorta in patients undergoing pulmonary vein isolation procedure for atrial fibrillation

INTRODUCTION

With the increasing use of pre-procedural imaging techniques such as magnetic resonance imaging (MRI) and their integration with electroanatomic mapping systems in catheter ablation for atrial fibrillation (AF), atypical anatomy of the pulmonary veins (PV), left atrium (LA) and their relationship to the thoracic aorta is increasingly recognized.

OBJECTIVE

To characterize atypical LA-PV anatomies revealed by pre-procedural MRI and their impact on the safety and efficacy of AF ablation procedures.

MATERIALS AND METHODS

We reported four patients who underwent AF ablation in our electrophysiology laboratory within the last year who had atypical LA-PV anatomy due to aorta compression recognized by pre-procedural three-dimensional (3D) MRI and anatomic segmentation. Twelve matched control cases without aorta compression were selected for comparison of LA-PV measurements.

RESULTS

All four patients in this study had a normal-sized descending thoracic aorta that compressed the left atrium, and all patients had evidence of left inferior PV narrowing secondary to external compression. Two patients also had anterior LA compression leading to posteriorly displaced interatrial septum. Isolation was not achieved in some PVs due to anatomic restraints, concern regarding risks of aortic injury and worsening pulmonary vein stenosis. There were no immediate or short-term complications.

CONCLUSIONS

Extrinsic compression by the descending aorta on the LA and PV leading to LA compression and/or preexisting PV stenosis is uncommon but has potentially important implications on the overall safety and efficacy of AF ablation procedures. Pre-procedural imaging plays an important role in assessing such anatomic variations and planning of the procedures in order to minimize the risk of PV stenosis and aortic injury.

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.

Postoperative asystole in a vasculopathic man

We present a case of postoperative cardiac arrest caused by extrinsic occlusion of the right coronary artery by an aortic pseudoaneurysm. Extrinsic impingement upon the coronary arteries may result from several etiologies and lead to cardiac symptoms identical to those caused by intrinsic coronary disease. Extrinsic compression may be amenable to treatment with angioplasty or a combination of angioplasty and surgery.

An unusual aneurysm of the main pulmonary artery presenting as acute coronary syndrome

A 70-year old man presented with retrosternal chest pain. His electrocardiogram showed nonspecific T wave changes. Cardiac-specific troponin I (cTnI) was elevated. His condition was managed as acute coronary syndrome, following which he had two minor episodes of hemoptysis. A CT pulmonary angiogram showed no evidence of pulmonary embolism, but a large mass lesion was seen in the mediastinum. Echocardiography and cardiac MRI demonstrated a large solid mass, arising from the right ventricular outflow tract and causing compression of the main pulmonary artery (MPA). The differential diagnosis included pericardial and myocardial tumors and clotted aneurysm of the MPA. At surgery, a clotted aneurysmal sac was identified originating from the MPA and the defect was healed. Aneurysms of the MPA are rare. They most commonly present with dyspnea and chest pain. Compression of surrounding structures produces protean manifestations. A high index of suspicion coupled with imaging modalities establishes the diagnosis. Blunt trauma to the chest, at the time of an accident 4 years previously, may explain this aneurysm. The patient's presentation with chest pain was probably due to compression and/or stretching of surrounding structures. Coronary artery compression simulating acute coronary syndrome has been documented in the literature. The rise in cTnI may have been due to right ventricular strain, as a result of right ventricular outflow obstruction by the aneurysm. This has not been reported previously in the literature. The saccular morphology and narrow neck of the aneurysm predisposed to stagnation leading to clotting of the lumen and healing of the tear, which caused the diagnostic difficulty.

Preexisting Pulmonary Vein Stenosis in Patients Undergoing Atrial Fibrillation Ablation: A Report of Five Cases

INTRODUCTION

Acquired pulmonary vein (PV) stenosis is a well-known complication following catheter ablation of atrial fibrillation (AF). However, the details of congenital PV stenosis have not been reported in patients who underwent catheter ablation of AF.

METHODS AND RESULTS

A total of 178 patients (110 men, age: 54 +/- 11 years) with drug-refractory AF received MRA or multidetector CT (MDCT) before ablation for delineation of PV morphologies. Five PVs in 5 patients (2.8%) showed at least 50% stenosis before ablation. We demonstrated two types of preexisting PV stenosis. Type I is the external compression of PV by the descending aorta, observed in LIPV of the three patients. Type II is the focal narrowing of PV, observed in RSPV of the two patients.

CONCLUSION

Preexisting stenosis of PV may be a consequence of congenital focal narrowing or external compression by the adjacent structures. Detection of this condition by 3D CT or MRA before catheter ablation can provide information for planning of ablation strategy and prevent misdiagnosis of ablation-related PV stenosis.