Coronary artery spasm after cardiac transplantation

Coronary Vasospasm Causing Chest Pain in Early Postoperative Heart Transplantation

Coronary vasospasm is a rare complication after heart transplant. Due to denervation of the donor heart, patients are typically asymptomatic but may present with cardiac arrhythmias or cardiac arrest. We present a patient with a recent heart transplant who experienced chest pain and was found to have coronary vasospasm.

A case report of cardiac allograft vasculopathy complicated with coronary vasospasm: insights from near-infrared spectroscopy, intravascular ultrasound, and optical coherence tomography

Background

Cardiac allograft vasculopathy (CAV) remains a major complication after heart transplantation. Although coronary vasospasm after heart transplantation has occasionally been reported, the association between CAV and coronary vasospasm remains unclear.

Case summary

A 68-year-old male with a history of heart transplantation 21 years ago presented with atypical angina. Coronary angiography demonstrated intermediate stenoses in the proximal and mid left anterior descending artery (LAD) and right posterolateral artery. Intracoronary acetylcholine provocation testing resulted in subtotal occlusion of the coronary arteries bilaterally, which was resolved by nitroglycerine administration, but the intermediate stenoses remained. The stenosis in the proximal LAD was physiologically significant based on fractional flow reserve. The patient was diagnosed with a developed CAV and concomitant coronary vasospasm and treated with percutaneous coronary intervention and nifedipine. Near-infrared spectroscopy and intravascular ultrasound showed a large isoechoic plaque with a low lipidic burden, suggesting a non-atherosclerotic plaque. Optical coherence tomography revealed a layered homogenous plaque, an intravascular imaging finding common in both CAV and coronary vasospasm. A drug-eluting stent dilated the stenosis, and follow-up angiography at 4 months showed no CAV progression.

Discussion

This case highlights the potential association between CAV and coronary vasospasm. Intravascular imaging detected similarities in plaque morphology between CAV and coronary vasospasm, suggesting that coronary vasospasm might contribute to the development of CAV. Although coronary vasospasm may be underdiagnosed in heart transplant recipients due to the lack of symptoms involving the denervated heart, this case showed that appropriate provocation testing may be beneficial for evaluating the cause of CAV.

Coronary Vasospasm Following Heart Transplantation: Rapid Progression to Aggressive Cardiac Allograft Vasculopathy

Coronary artery vasospasm (CVS) has been described in orthotopic heart transplant patients but is rare in the post-transplanted, denervated heart. Severe CVS has been associated with accelerated cardiac allograft vasculopathy (CAV) and allograft rejection. Allograft vasculopathy is the leading cause of decreased long-term survival in orthotopic heart transplant. The prognostic significance and relationship of the presence and severity of CVS with CAV are not well understood. We present a case of severe symptomatic CVS with rapid development of severe CAV. Our case emphasizes the need for close angiographic surveillance and intracoronary imaging for early detection of CAV in the presence of vasospasm.

Some observations on and controversies about coronary arterial spasm

The pathogenesis, clinical features, diagnosis, and treatment of spasm of epicardial coronary arteries are reviewed briefly, especially with regard to some issues that remain controversial. For diagnosis, emphasis is placed on the need for objective observations during an attack, even if that requires an attempt at pharmacologic provocation during coronary arteriography, or during echocardiography when prior arteriography has demonstrated the absence of severe coronary stenosis.

Variant angina associated with coronary artery endothelial dysfunction and myocardial bridge: a case report and review of the literature

The association of variant angina (VA) and myocardial bridges is a rare finding. We describe a case of VA with recurrent coronary spasm triggered by different stimuli at the site of a myocardial bridge. The interplay of endothelial dysfunction, coronary vasoconstriction and myocardial bridging was detected by intracoronary acetylcholine test and IVUS. We speculate that mechanical stimulation at the bridge site caused endothelial dysfunction and enhanced local susceptibility to vasoconstrictor stimuli. Variant angina should always be suspected in cases of ST-elevation acute coronary syndrome without any significant angiographic coronary stenosis.

Sirolimus as primary immunosuppression is associated with improved coronary vasomotor function compared with calcineurin inhibitors in stable cardiac transplant recipients

AIMS

The aim of this study was to evaluate coronary vasomotor function in cardiac transplant recipients maintained on sirolimus (SRL)- or cyclosporin (CyA)-based immunosuppression.

METHODS AND RESULTS

Endothelium-independent response to intracoronary nitroglycerin and adenosine and endothelium-dependent response to intracoronary acetylcholine (Ach) were assessed in 15 SRL- and 21 CyA- treated subjects with angiographically normal coronary arteries. Baseline mean blood pressure was lower in the SRL group (85.6 +/- 10.3 vs. 105.2 +/- 8.7 mmHg, P = 0.002). There was no difference between the groups in coronary flow reserve after adenosine administration in multivariable analysis (P = 0.34). Nitroglycerin administration resulted in increase in coronary artery diameter in the SRL compared with the CyA groups (2.79 +/- 0.54 vs. 2.57 +/- 0.61, P = 0.0036). In 13 SRL-treated subjects without evidence of cardiac allograft vasculopathy (CAV), Ach administration resulted in less epicardial vasoconstriction compared with CyA-treated subjects (2.7 +/- 17.7 vs. -15.6 +/- 17.2%, P = 0.005). Two SRL-treated subjects with three-dimensional intravascular ultrasound evidence of CAV developed coronary spasm in response to Ach 10(-4). Microvascular endothelial function did not differ between the groups.

CONCLUSION

Sirolimus immunosuppression is associated with less pronounced coronary epicardial endothelial dysfunction compared with CyA immunosuppression. Improvement of coronary vasomotor function with SRL may be an important mechanism for the prevention of CAV.

Coronary artery vasospasm causing acute myocardial infarction in a heart transplant recipient

The etiology of cardiac allograft vasculopathy is not known, but may be preceded by both endothelial cell and smooth muscle dysfunction of the epicardial coronary arteries. We here report a case of acute, reversible coronary artery vasospasm which caused a myocardial infarction in a cardiac transplant recipient. The patient had a complex post-transplant course, including an episode of severe vascular rejection several months before this presentation. Interestingly, the event was captured in its early stages because the patient presented with chest pain: a rare event because of the denervation of the transplanted heart. Our ability to document the etiology of this patient's myocardial infarction supports the concept that cardiac allograft vasculopathy is a progressive disease that, in its early stages, may include a reversible component of abnormal vasoreactivity.

Angiographic presentation of coronary artery spasm in heart transplant recipients

We describe the angiographic characteristics of coronary artery spasm observed in 12 out of 247 (4.9%) patients who underwent 808 coronary angiographies after heart transplantation. Coronary artery spasm was diagnosed when localized and reversible narrowing of the coronary lumen was identified. After coronary artery spasm identification all patients were followed-up clinically for a mean period of 5.1 years. Coronary artery spasm was documented 1-3 years after heart transplant. Coronary artery spasm affected 1 main coronary artery in 10 patients and 2 in 2 patients; in 3 patients 1 or more secondary branches were also affected. The right coronary artery was affected by coronary artery spasm in 8 patients and the anterior descending coronary artery in 6 patients. In 6 patients coronary artery spasm was mechanically induced by the catheter tip. The degree of luminal narrowing due to coronary artery spasm ranged from mild to almost complete occlusion. Coronary artery spasm appeared as a single tubular smooth and concentric stenosis in 8 patients, was discrete in 2 patients and multiple on the same vessel in 2 patients. In 1 patient coronary artery spasm was erroneously interpreted as an organic lesion and percutaneous transluminal coronary angioplasty was planned. During follow-up 3 patients out of 4 who had shown multiple coronary artery spasm died and 2 patients developed critical organic stenosis. In conclusion coronary artery spasm after heart transplant is less rare than commonly believed. Although it usually has a peculiar appearance, it can be misinterpreted as an organic lesion. Multiple coronary artery spasm appears to carry a poor prognosis.

Refractory vasospasm with a malignant course

We present a patient with two rare disorders, recurrent vasospastic angina leading to cardiac transplant and acute aortic occlusion. The patient had recurrent episodes of coronary vasospasm presenting with unstable angina, acute myocardial infarction, and sudden cardiac death in spite of adequate therapy with nitrates and calcium-channel blockers. He went on to have a cardiac transplant. The patient later presented with acute aortic occlusion with concomitant renal and mesenteric artery spasm. The circumstances of the presentation raise the possibility of a generalized vasospastic predisposition that is responsible for both events. Smoking, the only known major risk factor other than atherosclerosis, was noted to be temporally related to both events in our patient.

Coronary artery spasm in the transplanted human heart. A case report

This report describes a patient manifesting spontaneous and catheter-induced coronary artery spasm in a transplanted, denervated heart. This diagnosis should be considered in patients undergoing posttransplant coronary angiography. Intracoronary nitroglycerin should routinely be administered prior to coronary artery injections during posttransplant angiography.

Myocardial ischemia after cardiopulmonary bypass

Intraoperatively, myocardial ischemia is more common after cardiopulmonary bypass (CPB) than before CPB. Ischemia associated with coronary vasospasm and thrombosis may be much more common toward the end of surgery and early in the postoperative period than previously appreciated. This may be because the coagulation system is altered during CPB, and the coronary endothelium is damaged significantly as a result of cardioplegic arrest followed by reperfusion. In this milieu, vasospasm and thrombosis may be caused by the administration of protamine. Some of the ischemia observed in this period actually is not reversible and is associated with myocardial injury and infarction. It may be ameliorated by the administration of calcium channel blockers, aspirin, and anticoagulants. Electrocardiography may be the most suitable modality for the detection of ischemia after CPB and postoperatively. During this period, many episodes of ST deviation are of a nonischemic etiology, and the ECG needs careful interpretation. Transesophageal echocardiography is suitable for use intraoperatively and early on in the intensive care unit.

Sudden death in the young. Is acute coronary thrombosis the major precipitating factor?

BACKGROUND

Atherosclerotic coronary artery disease, complicated by acute thrombosis, is the usual cause of sudden death in adults. This study addresses the pathology of coronary arteries in sudden death in the young (< or = 35 years old).

METHODS AND RESULTS

Among 200 consecutive cases of sudden death in youth in the Veneto region of Italy, 37 (33 men and 4 women, age 18 to 35 years; mean, 29.4 years) showed obstructive atherosclerotic coronary artery disease in the absence of other cardiac pathological conditions and causes of death. No patient had previous angina pectoris or myocardial infarction. Cardiac arrest occurred at rest in 30 subjects and was related to effort in 7. A histological study was carried out on the obstructive coronary plaques. Degree of lumen stenosis and extension of lipid core and intimal fibrocellular hyperplasia facing the lumen were calculated morphometrically. Immunohistochemistry and electron microscopy were used to further characterize the plaque cell population. Single-vessel disease was found in 33 patients and triple-vessel disease in 4, with an overall total of 45 obstructive plaques, 34 of which were located in the proximal left anterior descending coronary artery. At histological study, only 10 plaques from 10 patients showed acute thrombosis (occlusive in 5 and subocclusive in 5); the remaining 35 were uncomplicated. Thirty-one plaques were fibrous in nature, while the other 14 were atheromatous. Compared with the atheromatous lesions, the fibrous plaques were rarely complicated by thrombosis (3% versus 64%; P < .001) and distinctly exhibited a fairly well-preserved tunica media (81% versus 21%; P < .001) as well as a stratum of neointimal fibrocellular hyperplasia (68% versus 7%; P < .001), which on immunohistochemistry and electron microscopy appeared to be proliferating smooth muscle cells.

CONCLUSIONS

In our study population, sudden death was precipitated by acute coronary thrombosis in only 27% of patients with obstructive coronary atherosclerotic plaque. Most of the young victims of sudden death with obstructive coronary atherosclerosis showed single-vessel disease that affected the left anterior descending coronary artery and was due to fibrous plaques with neointimal smooth muscle cell hyperplasia and a preserved tunica media in the absence of acute thrombosis.

Platelet aggregation and HDL cholesterol are predictive of acute coronary events in heart transplant recipients

BACKGROUND

Sudden death (SD) and acute myocardial infarction (AMI) are the main complications limiting long-term survival after heart transplantation (HT). They are unpredictable and, at present, unpreventable. Platelet aggregation (PA) has recently emerged as a significant prognostic indicator in nontransplanted coronary disease patients. The main purpose of the present study was to evaluate to what extent PA could predict SD and AMI in long-term survivors of HT independently of serum lipid levels.

METHODS AND RESULTS

We studied 207 patients. All received triple immunosuppressive therapy. During follow-up, the incidence of SD and AMI was determined, and the independent role of PA as predictor was evaluated with other usual risk factors by a Cox multivariate regression model. There were 11 SDs and 14 AMIs after an average follow-up of 642 days, giving an average incidence rate of 7.3 events per year per hundred patients. By univariate analysis, the most potent predictors were ADP-induced platelet aggregation (positive association) and total cholesterol (negative association). Age and length of time since transplant were not predictors. By multivariate analysis, only the secondary wave of ADP-induced platelet aggregation (P = .001) and high-density lipoprotein cholesterol (P = .03) were independent predictors. The relative risk of SD or AMI based on a comparison between patients with high (> 36%) or low (< 36%) ADP-induced platelet aggregation was 4.3 (95% confidence interval, 1.9 to 9.5, P = .0001).

CONCLUSIONS

This study provides the first demonstration of an association between increased platelet aggregation and subsequent SD or AMI in HT recipients. It suggests that platelets and thrombosis also are implicated in the pathogenesis of AMI and SD in HT recipients. Identification of a safe and effective antiplatelet therapy should be actively pursued.

Variant angina in an adolescent

We describe a case of variant angina associated with acute myocardial ischemia in an adolescent presenting with severe chest pain and transient ST elevation. Subsequent cardiac catheterization revealed normal coronary anatomy, and the patient has been asymptomatic since discharge on calcium channel blockers. Variant angina is a rare cause of chest pain in adolescents.

Absence of enhancement of spontaneous echocardiographic contrast by thrombocytosis in a patient with left ventricular aneurysm, primary thrombocythemia, and von Recklinghausen neurofibromatosis: a case report

A thirty-eight-year-old man with primary thrombocythemia, von Recklinghausen neurofibromatosis, and myocardial-infarction-related left ventricular aneurysm with spontaneous echocardiographic contrast was followed up, suggesting that: 1. Neurofibromatosis may promote silent myocardial infarction or ischemia. Whether involvement of cardiac sensory nerves is a possible underlying mechanism remains nevertheless uncertain. 2. Platelets, whose role in the genesis of spontaneous echocardiographic contrast has been advocated, are probably not involved in this phenomenon, even in large numbers.

The conduction system in transplanted hearts

This is a serial section examination of the conduction system (CS) in six patients who died seven months, 11 months, two years four months, four years two months, 11 years, and 16 years eight months following cardiac transplantation. The heart was hypertrophied and enlarged in all. There was myocarditis of varying degree in all cases with arteriosclerosis and arteriolosclerosis. These findings were more dominant in the atria than in the ventricles. In the CS, myocarditis with fibrosis was found in all in the approaches to the sinoatrial (SA) node, the SA node, the atria, the atrioventricular (AV) node, and the bundle and bundle branches, to a varying degree. When compared with the endomyocardial biopsy findings, the autopsied cases revealed more myocarditis and fibrosis than those estimated to be present in the biopsy specimen. In summary, this study demonstrates that there are fibrotic changes in the CS with the persistence of inflammatory phenomena of the myocardium and the CS to a varying degree in transplanted hearts. This is accompanied by the ubiquitous coronary artery disease affecting not only the large coronaries but also the small vessels. The pathologic changes in and around the CS may be responsible for arrhythmias and sudden death in some cases of cardiac transplantation.