Left ventricular long axis disturbances as predictors for thallium perfusion defects in patients with known peripheral vascular disease

Abstract

Objective-To compare resting long axis echocardiography with adenosine thallium-201 emission tomography in detecting myocardial ischaemic abnormalities in patients before peripheral vascular surgery. Design-A prospective and blinded preoperative examination of resting left ventricular minor and long axes and myocardial perfusion during adenosine vasodilatation using thallium-201 emission tomography. Setting-A tertiary referral centre for cardiac and vascular disease equipped with invasive, non-invasive, and surgical facilities. Subjects-65 patients (40 men) with significant peripheral vascular disease, mean (SD) age 63 (10) years, and 21 control subjects of similar age. Methods-Segments were classified as normal, with fixed or reversible defects according to thallium-201 myocardial perfusion tomography. Systolic long axis abnormalities were either reduced excursion and/or abnormal shortening after A2, and diastolic abnormalities either delayed onset of lengthening > 80 ms and/or reduced peak lengthening rate < 4.5 cm/s. Segmental perfusion defects were compared with the equivalent long axes; anteroseptal for septal, inferoseptal for posterior, and lateral for left side giving a total of 195 segments. Results-Systolic long axis abnormalities predicted fixed thallium defects (sensitivity 86%, specificity 87%, positive predictive value 0.78, negative predictive value 0.93, p < 0.001), and diastolic abnormalities correlated with reversible perfusion defects (sensitivity 90%, specificity 85%, positive predictive value 0.72, negative predictive value 0.95, p < 0.001). Echocardiography characteristics of the true and false positive segments were not diVerent in the site or the extent of abnormalities. Conclusion-Systolic long axis abnormalities predict fixed and diastolic reversible thallium perfusion defects in patients with peripheral vascular disease. Ventricular long axis may thus have a value as a screening test before peripheral vascular surgery as well as providing a means of monitoring myocardial perfusion. The high negative predictive values indicate that a negative long axis study makes significant perfusion abnormalities very unlikely in patients with high pretest probability of coronary artery disease. (Heart 1998;79:295-300)

Use of quantitative two-dimensional color tissue Doppler imaging for assessment of left ventricular radial and longitudinal myocardial velocities in dogs

“…Moreover, in pathologic conditions such as myocardial ischemia or hypertrophy, the longitudinal LVFW function is impaired before abnormalities in radial motion develop, and assessment via TDI could enhance early diagnosis of myocardial alterations. 7,22,23 Longitudinal myocardial alteration has been reported in a canine model of dilated cardiomyopathy (Golden Retriever muscular dystrophy [GRMD]). 24 In that report, young dogs affected by GRMD had low systolic basal and apical velocities and low basal velocity in early diastole, despite an absence of ventricular dilatation or alterations in inotropism.…”

Long axis function in disease

“…It is aggravated by balloon inflation during coronary angioplasty,12 and invariably resolves within 48 hours of a successful procedure 13. The presence and location of asynchrony correlates closely with reversible abnormalities on thallium myocardial perfusion scanning 8. Asynchrony occurs in the absence of symptoms or ECG changes, and thus provides the most sensitive non-invasive evidence of ischaemia.…”

Abnormalities of right ventricular long axis function after atrial repair of transposition of the great arteries

“…Myocardial fibres also run in a longitudinal fashion in the subendocardial and subepicardial planes of the LV. Analysis of these myocardial fibres is sensitive for showing LV disease 10. The majority of RV myocardial fibres originate at the apex of the heart and insert into the right atrioventricular junction, such that the main bulk of the RV myocardium is composed of longitudinally arranged fibres 9.…”