Coronary arterial involvement in aortitis syndrome: Assessment by exercise thallium scintigraphy

Findings of cardiac magnetic resonance imaging in asymptomatic myocardial ischemic disease in Takayasu arteritis

Takayasu arteritis (TA) may affect myocardium and cause coronary stenosis. The aim of this study was to assess the prevalence and pattern of myocardial disease in patients with TA, using late gadolinium enhancement (LGE) of cardiac magnetic resonance imaging (CMRI). Twenty-seven consecutive patients with TA and 80 age- and gender-matched controls without known cardiovascular disease underwent CMRI. The prevalence of myocardial ischemic disease, as revealed by LGE, was compared between patients with TA and controls, and factors associated with myocardial disease were identified in patients with TA. Myocardial ischemic disease, as characterized by LGE on CMRI, was present in 7 (25.9%) of 27 patients with TA, and imaging with LGE showed a typical pattern of myocardial infarction in 6 patients (22.2%). Although both patients with TA and control subjects shared a similar risk of cardiovascular events, the prevalence of myocardial ischemia was >5× greater in patients with TA (p = 0.002 vs controls). No association was found between myocardial disease in patients with TA and cardiovascular atherosclerotic risk factors. The presence of myocardial scarring tended to be more closely associated with specific features of TA such as renovascular hypertension, older age at the onset of TA symptoms, male gender, aneurysmal dilatation, and Numano type V. In conclusion, finding of a significant and unexpectedly high prevalence of occult myocardial scarring in patients with TA indicates the usefulness of CMRI with LGE for the identification of occult myocardial disease in such patients.

Myocardial Perfusion Imaging in Takayasu Arteritis

Objective.

Myocardial perfusion defects using scintigraphy have been frequently observed in patients with Takayasu arteritis (TA) without coronary stenosis. The aim of our study was to evaluate coronary microcirculation in TA using thallium-201 (201Tl) myocardial scintigraphy and dipyridamole (DPM) as vasodilator agent.

Methods.

Twenty-five consecutive patients with TA were prospectively recruited. They were asymptomatic for cardiac issues and examined using 201Tl myocardial scintigraphy at rest and after coronary artery vasodilation with intravenous DPM. Factors associated with improvement in myocardial perfusion after DPM were identified in patients with TA.

Results.

Among 25 patients with TA, 21 (84%) had 201Tl myocardial perfusion defects and 4 (16%) had normal resting myocardial perfusion. Using a 17-segments model for quantitative image analysis, DPM significantly improved resting 201Tl myocardial perfusion in 14 patients (61%) versus 9 patients without improvement (39%). We were able to examine coronary artery stenoses in 11 patients, including 10 patients with thallium perfusion defects, and significant coronary artery stenoses were present in only 2 patients (18.2%). No significant difference was found in traditional cardiovascular risk factors between TA patients with or without improvement of myocardial perfusion after DPM. The absence of improvement in myocardial perfusion after DPM tended to be closely associated with specific features and prognostic factors of TA, such as aortic regurgitation at diagnosis, renovascular hypertension, longer duration of TA disease, and male sex.

Conclusion.

We found the significantly high prevalence of myocardial perfusion defects mostly improved after vasodilation with DPM, which may indicate the major role of microcirculatory dysfunction in myocardial ischemia in TA.

Takayasu arteritis in Thailand: clinical and imaging features

PURPOSE

To present and evaluate the clinical and imaging features of patients with Takyasu arteritis in Thailand.

MATERIALS AND METHODS

Clinical and angiographic findings were studied in 63 patients with Takayasu arteritis collected at Chulalongkorn Hospital Medical School, Bangkok. Imaging features including CT scan in 15 patients, magnetic resonance imaging in 14 patients and magnetic resonance angiography in ten patients were evaluated and compared to angiography.

RESULTS

Among 63 patients there were 43 females and 20 males with the ratio female to male 2.15:1. The most common age groups were in the third and fourth decades of life. The most common clinical findings were hypertension and absence or weakness of pulses. Elevated erythrocyte sedimentation rate was found in 50%. For angiography, the most common vessel affected was the abdominal aorta (20%). The second and third most common sites were renal arteries (18.7%) and the subclavian arteries (14.3%). Coronary artery involvement was found in two out of eight patients. No pulmonary involvement was found in eight cases studied by pulmonary angiography. For classification of angiogram, the most common type of involvement (66.7%) was extensive involvement of the aorta and branches (type V of new classification established from International Conferences on Takayasu arteritis in Tokyo 1994). No patient was found to have only involvement of brachiocephalic branches or ascending aorta and brachiocephalic branches. CT scan showed calcification in the vessel walls (8/15 cases) which helped in diagnosis of the disease. Wall thickness, surrounding tissue, appearance of the vessel and intraluminal thrombus could be well seen. Magnetic resonance imaging added more detail in multiple planes and could demonstrate vascular flow. High detection rate of the lesions (94.8%) was found for the aorta. The study was less sensitive for smaller vessels. Magnetic resonance angiography showed better correlation of the findings of brachiocephalic arteries compared to angiography. Subclavian steal syndrome could be diagnosed. For renal arteries, MR angiography could correctly demonstrate occlusion of renal artery in six out of eight cases. In the other two cases only stenoses of the vessels were found on angiograms. One renal arterial stenosis on MR angiography was confirmed by angiography.

CONCLUSION

Takayasu arteritis could be found in Thailand. Clinical features were almost the same as in reports from other countries. Various forms of arterial involvement were demonstrated by imaging modalities. Angiography remained the best method for detection and diagnosis of Takayasu arteritis in correlation with clinical and laboratory findings. Although CT scan, magnetic resonance imaging and magnetic resonance angiography were limited and less sensitive for detection of the lesions, they were useful as noninvasive modalities showing more details of intraluminal clot, vascular wall and surrounding tissue which could be correlated with pathological findings and pathogenesis of the disease. Our study suggests that MR imaging and MR angiography can be screening and diagnostic techniques for patients with suspected Takayasu arteritis.

Systemic manifestations of Takayasu arteritis: the expanding spectrum

Takayasu arteritis (TA) is a chronic inflammatory and obliterative disease of large vessels particularly the aorta and its major branches. Recently, the disease has been shown to involve the parenchyma of various organs. Specific glomerular lesions reported in patients with TA are mesangial proliferative, membrano-proliferative, crescentic glomerulonephritis and amyloidosis. Dermatological manifestations of this disease are erythema nodosum, facial lupus rash and erythema induratum. Dilated cardiomyopathy, myocarditis and pericarditis have been reported in TA. Rarely, interstitial lung disease, pneumonic consolidation, idiopathic ulcerative colitis, rheumatoid arthritis and polymyositis have been described in association with TA. In this report, five patients of TA with primary parenchymatous involvement of kidneys, skin, heart and gastrointestinal tract have been described. An association of primary parenchymatous organ involvement and TA suggests an autosensitization to an unidentified antigen in the pathogenesis of TA.