Aerobic high-intensity interval exercise training in patients with angina and no obstructive coronary artery disease: feasibility and physiological effects.

Aims: Patients with chest pain and normal coronary angiogram [angina with normal coronary arteries (ANOCA)] constitute a therapeutic problem with considerable functional limitation and reduced quality of life. The aims of the current pilot study were to (i) explore if a structured aerobic high-intensity interval training (HIT) program for 12 weeks was feasible in patients with ANOCA, and (ii) to assess mechanisms related to symptoms in this population. Methods and results: Sixteen patients with ANOCA underwent a 3-month aerobic HIT program with one-to-one monitored exercise sessions on treadmill in a 4 min × 4 manner, three times a week. Four patients served as controls. Coronary flow velocity reserve (CFVR) transthoracic Doppler, flow-mediated vasodilation (FMD) and VO2max was measured at baseline and after 12 weeks. The average attendance to training sessions was 82.3% ± 10.1 (56-94). CFVR in the training group increased from 2.50 ± 0.48 to 3.04 ± 0.71 (P < 0.001) whereas FMD increased from 4.19 ± 2.42% to 8.28 ± 2.85% (P < 0.001). Improvement in CFVR correlated with the relative improvement in FMD (R = 0.45, P = 0.047). This was associated with an increase in VO2max from 28.75 ± 6.51 mL/kg/min to 31.93 ± 6.46 mL/kg/min (P < 0.001). Conclusion: A 3-month program of monitored HIT was feasible, with high adherence resulting in improved functional capacity in patients with ANOCA. CFVR improved and this improvement was associated with improved FMD. ClinicalTrialsgov Identifier: NCT02905630.

Natural Course of Electrocardiogram Changes and the Value of Multimodality Imaging in Acute Pericarditis.

BACKGROUND: ECG is the initial diagnostic tool that in combination with typical symptoms often raises the suspicion of pericarditis. Echocardiography remains the first-line imaging modality for assessment of pericardial diseases, particularly effusion/tamponade, constrictive physiology, and assessment of regional wall motion abnormalities as differential diagnoses. However, cardiac CT and cardiac magnetic resonance may be necessary in complicated cases and to identify pericardial inflammation in specific settings (atypical presentation, new onset constriction), as well as myocardial involvement and monitoring the disease activity. SUMMARY: In acute pericarditis, the most commonly used ECG criteria recommended by international guidelines are the widespread ST-segment elevation or PR depression. However, the classic ECG pattern of widespread ST-segment elevation or PR depression can be seen in less than 60% of patients. In addition, ECG changes are often temporally dynamic, evolve rapidly during the course of disease, and may be influenced by a number of factors such as disease severity, time (stage) of presentation, degree of myocardial involvement, and the treatment initiated. Overall, temporal dynamic changes on ECG during acute pericarditis or myopericarditis have received limited attention. Hence, the aim of this brief clinical review was to increase awareness about the various ECG changes observed during the course of acute pericarditis. KEY MESSAGES: ECG may be normal at presentation or for days after the index episode of chest pain, but serial ECGs can reveal specific patterns of temporally dynamic ST elevation in patients with pericarditis or myopericarditis, particularly during new episodes of chest pain.

Echocardiographic features of left ventricular recess, cleft, diverticulum, and aneurysm: A systematic review.

A pouch protruding into the wall of the left ventricle (LV) may be either a recess, cleft, diverticulum, or aneurysm. Being aware of these anomalies is essential to make accurate diagnosis and guide management decisions. Standard multimodality imaging of the heart enables detailed characterizations of LV fissures and outpouchings. They often present as an incidental finding on echocardiography, and the clinical significance can be difficult to address. We provide an overview of echocardiographic features of LV recess, cleft, diverticulum, pseudoaneurysms/aneurysms, and non-compaction based upon review of the literature as well as present some relevant clinical cases from our echocardiography labs.

Usefulness of Stress Echocardiography in Assessment of Dynamic Left Ventricular Obstructions: Case Series and Review of the Literature.

Dynamic left ventricular outflow tract obstruction (DLVOTO) or midcavity obstruction in patients with structurally normal hearts is not uncommon in routine clinical practice and can cause significant symptoms mimicking coronary artery disease or heart failure. Although exercise echocardiography is the gold standard for assessing DLVOTO, dobutamine stress echocardiography (DSE) may be valuable diagnostic modality in patients who are unable to exercise or have an uninterpretable 12-lead electrocardiogram. We provide an updated overview of the relevant literature regarding prevalence, pathophysiology, clinical significance, and prognostic impact of DLVOTO and midcavity obstruction in structurally normal hearts. We also present a clinical series of 4 cases of DLVOTO and midcavity obstruction documented by DSE and discuss the value of different kinds of modern stress imaging modalities involving: (1) contrast-enhanced DSE to assess myocardial perfusion and inducible ischemia; (2) adenosine stress echocardiography to assess coronary flow reserve/microvascular dysfunction; and (3) functional imaging with deformation echocardiography to assess subclinical myocardial dysfunction in patients with structurally normal heart and without significant coronary disease. Based upon our own experiences and a critical review of the current literature, we will then present a practical guidance for management of DLVOTO and midcavity obstruction.

A woman in her fifties with left bundle branch block and recurrent arrhythmias. / En kvinne i 50-årene med venstre grenblokk og tilbakevendende arytmier.

BACKGROUND: Sarcoidosis is a multi-system inflammatory disorder resulting in the formation of non-caseating granulomas in various parts of the body. Cardiac involvement is associated with worse prognosis, probably due to the destructive effects the granulomas can have on the electrical conduction system. The diagnosis of cardiac sarcoidosis can be challenging due to the limited accuracy of various clinical criteria. CASE PRESENTATION: A woman in her fifties developed symptoms in the form of dry cough and uncharacteristic chest pain. Thorough assessment was initiated, but the true cause remained undiagnosed for several years. The patient suffered from recurrent arrythmias and eventually a weakened ventricular function and cardiac failure. A multidisciplinary approach revealed that the patient was suffering from cardiac sarcoidosis. INTERPRETATION: Cardiac sarcoidosis may initially present with mild symptoms, but left bundle branch block, total AV-block and supraventricular tachycardias, as well as weakened ventricular function, should raise suspicion of the condition. Magnetic resonance imaging and echocardiography may be of help during clinical assessment, and positron emission tomography/computed tomography and biopsy can confirm the condition.

Nephrotic syndrome and pulmonary hypertension as complications of intravenous drug abuse.

This case report discusses a patient with nephrotic syndrome, pulmonary hypertension, and repeated episodes of infections. He had a history of intravenous drug abuse. Kidney biopsy revealed the rare finding of numerous foam cells, mainly in glomeruli. The solvent used for the drugs is thought to be responsible for the foam cells. In line with previous reports, we suspect that the pulmonary hypertension is consistent with foam cells in pulmonary capillaries or fat embolism syndrome due to the intravenous administered drugs. Our case demonstrates that the use of intravenous drugs can lead to widely varying symptoms. Globally, the prevalence of substance abuse is increasing. Knowledge about their damaging effects is crucial in both clinical practice and anatomic pathology.

Constrictive pericarditis as a rare cause of chylothorax: a case report.

BACKGROUND: Chylothorax is a rare clinical condition that results from thoracic duct damage with leakage of chyle from the lymphatic system to the pleural space. Rarely, constrictive pericarditis has been associated with chylothorax, but to our knowledge only in relation to secondary causes such as tuberculosis, HIV, or malignancy. CASE SUMMARY: A previously healthy 63-year-old man presented with effusive-constrictive pericarditis, recurrent right-sided pleural effusion, and chylothorax. There was no history of co-morbidities, surgical illness, or cardiac procedures. No single aetiologic factor was identified despite comprehensive assessment. Substantial immunosuppressive therapy was given without a sufficient clinical response. Pericardiectomy resulted in resolution of the constrictive haemodynamics and terminated chylous effusion. DISCUSSION: The hypothesized mechanisms for development of chylothorax in association with constrictive pericarditis are the increased effective capillary infiltration secondary to central venous hypertension and reduced lymphatic drainage due to high pressure in the left subclavian vein. Increased capillary filtration may result in excessive lymph formation. However, the mechanism is not completely understood.

Transthoracic Doppler for detection of stenoses in the three main coronary arteries by use of stenotic to prestenotic velocity ratio and aliased coronary flow.

AIMS: Our aim was to determine the feasibility and accuracy of diagnosing significant coronary artery stenoses using peak stenotic to prestenotic velocity ratio (pSPVR) measurements when compared with results from quantitative coronary angiography and coronary flow velocity reserve (CFVR) assessed by transthoracic echocardiography (TTE). METHODS AND RESULTS: One hundred and eight patients scheduled for coronary angiography were studied using transthoracic Doppler echocardiography. Stenoses were identified by local colour aliasing by colour flow Doppler, and further evaluated by pSPVR, using a pSPVR of ≥2.0 as a cut-off for significant stenosis. When pSPVR could not be measured, local mosaic coronary flow pattern at Nyquist limit ≥0.48 m/s was used. Sixty-five lesions suggestive of stenosis were found by TTE. Combining findings of pSPVR ≥2.0 and local mosaic flow at Nyquist limit ≥0.48 m/s, the sensitivity and specificity of demonstrating significant stenoses (diameter stenosis, 50-99%) in the left main coronary artery (LM), left anterior descending coronary (LAD), left circumflex coronary (Cx), and right coronary artery (RCA) were 75 and 98%, 74 and 95%, 40 and 87%, and 34 and 98%, respectively. The pSPVR did not differ significantly between arteries with reduced and normal CFVR, with a cut-off of CFVR <2.0. CONCLUSIONS: Findings of pSPVR ≥2.0 or localized colour flow aliasing are useful in the non-invasive diagnosis of significant coronary disease in the three main coronary arteries, with high specificity for detecting significant stenoses. These findings showed high sensitivity for identifying significant stenoses in the LM and LAD, but showed lower ability to detect those lesions in the Cx and RCA.

Coronary artery occlusions diagnosed by transthoracic Doppler.

BACKGROUND: Our aim was to assess whether anterograde flow velocities in septal perforating branches could identify an occluded contralateral coronary artery, and to assess the feasibility and accuracy of diagnosing occlusions in the three main coronary arteries by the combined use of several noninvasive parameters indicating collateral flow. METHODS: A total of 108 patients scheduled for coronary angiography because of chest pain or acute coronary syndromes were studied using transthoracic Doppler echocardiography. RESULTS: Anterograde peak diastolic flow velocities (pDV) in septal perforating branches were higher in patients with angiographic occluded contralateral artery compared with corresponding velocities in patients without significant disease in the contralateral artery (0.80 ± 0.31 m/sec versus 0.37 ± 0.13 m/sec, p < 0.001). Receiver operating characteristic curve showed pDV ≥ 0.57 m/sec to be the optimal cutoff value to identify occluded contralateral artery, with a sensitivity of 79% and a specificity of 69%. Demonstration of at least one positive parameter (retrograde flow in main coronary arteries, reversed flow in septal perforating and left circumflex marginal branches, pDV ≥ 0.57 m/sec, or demonstration of other epicardial or intramyocardial collaterals) indicating collateral flow to an occluded main coronary artery had sensitivity, specificity, positive and negative predictive value of 89%, 94%, 63%, and 99%, respectively, for detection of a coronary occlusion. With this combined use of several parameters, 25 of 28 coronary occlusions were identified. CONCLUSIONS: By investigating several parameters indicating collateral flow, we were able to identify most of the main coronary occlusions in the patient cohort. Furthermore, our study demonstrated that coronary artery occlusions may result in complex and diverging coronary pathophysiology depending on which coronary artery segment is occluded and the extent of accompanying coronary artery disease. TRIAL REGISTRATION: ClinicalTrials.gov number NTC00281346.

Transthoracic Doppler echocardiography for detection of stenoses in the left coronary artery by use of poststenotic coronary flow profiles: a comparison with quantitative coronary angiography and coronary flow reserve.

BACKGROUND: The aim of this study was to determine whether poststenotic diastolic-to-systolic velocity ratio (DSVR) assessed by transthoracic Doppler echocardiography could accurately identify significant stenoses in the left coronary artery. METHODS: A total of 108 patients scheduled for coronary angiography because of chest pain or acute coronary syndromes were studied. RESULTS: The success rates of peak DSVR (pDSVR) measurements in the distal to mid left anterior descending coronary artery and marginal branches of the left circumflex coronary artery were 85% and 32%, respectively. With peak coronary flow velocity reserve as a reference, pDSVR was significantly higher in arteries with normal coronary flow reserve (peak coronary flow velocity reserve ≥ 2.0) compared with arteries with reduced coronary flow reserve (peak coronary flow velocity reserve < 2.0) (1.86 ± 0.32 vs 1.53 ± 0.31, P < .0001). In comparison with quantitative coronary angiography, pDSVR was significantly higher in lesions with diameter stenosis < 50% compared with those with diameter stenosis of 50% to 75% (1.92 ± 0.32 vs 1.53 ± 0.18, P < .0001) or diameter stenosis of 76% to 100% (1.43 ± 0.13, P < .0001). Receiver operating characteristic curves showed pDSVR < 1.68 to be the optimal cutoff value for identifying both functionally significant stenoses and diameter stenoses ≥ 50%, with sensitivity of 86% and 90%, specificity of 74% and 84%, positive predictive value of 51% and 71%, and negative predictive value of 94% and 95%, respectively. CONCLUSIONS: Transthoracic pDSVR measurements in the distal to mid left anterior descending coronary artery and marginal branches of the left circumflex coronary artery had high accuracy for excluding functionally significant stenoses in the left coronary artery, as well as for identifying angiographic significant stenoses.

Coronary flow velocity reserve in the three main coronary arteries assessed with transthoracic Doppler: a comparative study with quantitative coronary angiography.

BACKGROUND: The purpose of this study was to evaluate the potential of combined use of transthoracic Doppler echocardiographic coronary flow velocity reserve (CFVR) measurements and findings of retrograde coronary flow in the three main coronary arteries for the assessment of borderline (angiographic diameter stenosis, 50%-75%) and high-grade (angiographic diameter stenosis, 76%-100%) coronary artery stenoses. METHODS: A total of 108 patients scheduled for coronary angiography because of chest pain or acute coronary syndromes were studied. CFVR was measured during adenosine-induced hyperemia in the mid to distal segments of the left anterior descending coronary artery, the marginal branches of the left circumflex coronary artery, and the posterior descending coronary artery, with peak CFVR (pCFVR) <2.0 implying hemodynamic significant stenosis. CFVR results were compared with results from quantitative coronary angiography, with stenosis severity in the left main and three major coronary arteries divided into three groups: (1) diameter stenosis 0% to 49%, (2) diameter stenosis 50% to 75%, and (3) diameter stenosis 76% to 100%. RESULTS: In patients with antegrade flow in the relevant coronary artery segment, CFVR was successfully measured in the mid to distal left anterior descending artery, the marginal branches of the left circumflex artery, and the posterior descending artery in 97%, 63%, and 75% of patients, respectively. CFVR was significantly different among the stenosis groups, with pCFVR of 2.79 ± 0.77 in group 1, 2.01 ± 0.72 in group 2, and 1.50 ± 0.69 in group 3 (P < .001 among groups). Angiography confirmed retrograde flow in seven of the nine arteries found by transthoracic echocardiography. Findings of pCFVR <2.0 or retrograde coronary artery flow correctly identified 42 of 49 patients with stenoses in group 3, with sensitivity, specificity, and positive and negative predictive values of 86%, 70%, 70%, and 85%, respectively. In group 2, pCFVR values were widely distributed above or below the defined pCFVR cutoff value. CONCLUSIONS: CFVR measurement in the mid to distal left anterior descending artery was feasible in almost all patients, and in the marginal branches of the left circumflex artery and the posterior descending artery in two thirds and three quarters of patients, respectively. Use of the combined echocardiographic criteria had high precision for diagnosing severe coronary stenoses (diameter stenosis, 76%-100%). The functional significance of angiographically borderline stenoses (diameter stenosis, 50%-75%) may be further differentiated by the use of CFVR measurements.

Transthoracic echocardiography for imaging of the different coronary artery segments: a feasibility study.

BACKGROUND: Transthoracic echocardiography (TTE) may be used for direct inspection of various parts of the main coronary arteries for detection of coronary stenoses and occlusions. We aimed to assess the feasibility of TTE to visualise the complete segments of the left main (LM), left descending (LAD), circumflex (Cx) and right (RCA) coronary arteries. METHODS: One hundred and eleven patients scheduled for diagnostic coronary angiography because of chest pain or acute coronary syndrome had a TTE study to map the passage of the main coronary arteries. LAD, Cx and RCA were each divided into proximal, middle and distal segments. If any part of the individual segment of a coronary artery with antegrade blood flow was not visualised, the segment was labeled as not satisfactorily seen. RESULTS: Complete imaging of the LM was achieved in 98% of the patients. With antegrade directed coronary artery flow, the proximal, middle and distal segments of LAD were completely seen in 96%, 95% and 91% of patients, respectively. Adding the completely seen segments with antegrade coronary flow and segments with retrograde coronary flow, the proximal, middle and distal segments of LAD were adequately visualised in 96%, 96% and 93% of patients, respectively. With antegrade directed coronary artery flow, the proximal, middle and distal segments of Cx were completely seen in 88%, 61% and 3% and in RCA in 40%, 28% and 54% of patients. Retrograde coronary artery flow was correctly identified as verified by coronary angiography in seven coronary segments, mainly in the posterior descending artery (labeled as the distal segment of RCA) and distal LAD. CONCLUSIONS: TTE is a feasible method for complete demonstration of coronary flow in the LM, the proximal Cx and the different segments of LAD, but less suitable for the RCA and mid and distal segments of the Cx. (ClinicalTrials.gov number NTC00281346.).

[Noncompaction of the left ventricular myocardium]. / Manglende modning av venstre ventrikkels myokard.

BACKGROUND: Noncompaction of the left ventricular myocardium is recently described as a cause of left ventricular dysfunction. In the article, we describe epidemiological and clinical aspects of this condition, which presents clinically at any age. MATERIAL AND METHODS: This article is based on a review of articles from our own literature archive and relevant references in these articles. RESULTS: Ventricular noncompaction results from an arrest in the normal endomyocardial embryogenesis, and often leads to heart failure, thrombo-embolic events and/or ventricular arrhythmias. The disorder is diagnosed by two-dimensional echocardiography or magnetic resonance imaging of the heart. The changes are typically seen in the apex and distal and middle segments of the inferior and lateral walls of the left ventricle. The affected segments of the myocardium have a two-layered structure: a compacted thin epicardial layer and an endocardial layer consisting of a prominent trabecular meshwork with deep intertrabecular spaces. The condition can be isolated with or without extracardiac disorders, or can be associated with other cardiac malformations. INTERPRETATION: It is essential not to miss the findings of noncompaction, as the condition may lead to serious heart failure, thrombo-embolic events, ventricular tachyarrythmias or death. Early recognition of noncompaction may give better follow-up and management of patients with this condition.

Direct visualization of a significant stenosis of the right coronary artery by transthoracic echocardiography. A case report.

Non-invasive imaging of coronary arteries by transthoracic echocardiography is an emerging diagnostic tool to study the left main (LM), left descending artery (LAD), circumflex (Cx) and right coronary artery (RCA). Impaired coronary circulation can be assessed by measuring coronary velocity flow reserve (CVFR) by transthoracic Doppler echocardiography. Coronary artery stenoses can be identified as localized colour aliasing and accelerated flow velocities. We report a case with an acute coronary syndrome (ACS) of a 46-year-old man. With non-invasive imaging of coronary arteries by transthoracic echocardiography (TTE), we identified a segment of the mid right coronary artery (RCA) suggestive of stenosis with localized colour aliasing and accelerated flow velocity. We found a high ratio between the stenotic peak velocity and the prestenotic peak velocity, and a pathologic coronary flow velocity reserve (CFVR) distal to the stenosis in the posterior interventricular descending branch (RDP). Subsequent coronary angiography demonstrated one vessel disease with a stenosis in segment 3 of RCA, which was successfully treated with percutaneos coronary intervention PCI. Two weeks following the PCI procedure he was readmitted to hospital with chest pain. A subacute stent thrombosis was questioned, and repeated echocardiography was preformed. The mid portion of RCA showed normal and laminar flow. The CVFR of RCA measured in the RDP showed normal vasodilatory response, confirming an open RCA without any flow limitation. A repeated coronary angiogram demonstrated only a mild in stent intimal hyperplasia. This case illustrates the value of transthoracic echocardiography as a tool both in the diagnosis and the follow-up of chest pain disorders and coronary flow problems. Transthoracic echocardiography allows both direct visualization of the various coronary segments and assessment of the CVFR.

[Congestive heart failure--etiology and diagnostic procedures]. / Kronisk hjertesvikt--etiologi og diagnostikk.

Congestive heart failure is a major health problem in the western world and the prevalence of patients with this diagnosis increases. About 2% of the adult population are affected; the majority are elderly, which represents a challenge when it comes to assessment and treatment. This article concerns the aetiology and diagnosis of congestive heart failure and provides a suggestion for guidelines. The proposed guidelines are aimed at primary, secondary and third line health care providers in Norway, and are based on previously published Norwegian guidelines and international guidelines. Hypertension and coronary artery disease account for 75-80% of known cases of congestive heart failure. The patient's history and risk factors must be investigated. Laboratory tests emphasising organ functions are important, and these should include measurement of B-type natriuretic peptide (BNP). Electrocardiograms and chest X-rays should be taken as well. All patients with suspected impaired left ventricular ejection fraction should undergo an echocardiographic examination. Invasive tests, and non-invasive imaging should be used for selected groups of patients only.

[Treatment of congestive heart failure]. / Behandling av kronisk hjertesvikt.

The Working Group on Heart Failure of the Norwegian Society of Cardiology here presents a revised programme for the treatment of congestive heart failure. Possible surgical and percutaneous interventions should be considered, and non- pharmacological measures taken as indicated for each patient. ACE-inhibitors are the first-line pharmacological therapy in heart failure with reduced left ventricular ejection fraction (< 40%). Possible adverse effects on blood pressure, renal function and electrolytes necessitate close monitoring of these variables. Beta-blockers should be considered in patients with symptomatic heart failure. If ACE-inhibitors are not tolerated, an angiotensin- II-blocker can be the added. Diuretics should only be used as adjunctive therapy to ACE-inhibitors. Aldosterone antagonists have a proven effect on survival, but close monitoring of potassium levels is imperative. Especially in the elderly, the renal function and level of electrolytes must be monitored closely. Device therapy, such ac cardiac resynchronization therapy and implantable cardioverter defibrillators, are only indicated for selected patients. ACE-inhibitors, diuretics and beta-blockers are the drugs-of-choice for patients with congestive heart failure with preserved systolic function. Health care for patients with congestive heart failure must be well organized on different levels of care and with multidisciplinary teams involved. The goal is to reduce morbidity and mortality in the heart failure population. This programme is meant for primary, secondary and third line health care providers in Norway.

Long-term echocardiographic follow-up of a patient with primary pulmonary hypertension receiving iloprost inhalations.

Iloprost inhalation has recently emerged as an alternative therapy for severe primary pulmonary hypertension. In the studies documenting the effect of iloprost inhalation therapy, hemodynamic variables have been measured invasively. We have followed a patient with primary pulmonary hypertension receiving iloprost inhalation therapy for 5 years using echocardiography to monitor changes in pulmonary artery pressure and right ventricular function. Echocardiography was also used to evaluate the initial response to iloprost inhalation therapy. This case illustrates the feasibility and utility of echocardiography in the testing and follow-up of iloprost inhalation therapy in patients with pulmonary hypertension.

Estimation of left ventricular ejection fraction from Doppler derived myocardial performance index in patients with acute myocardial infarction: agreement with echocardiographic and radionuclide measurements.

OBJECTIVE: The aim of the study was to validate a previously published method to calculate left ventricular ejection fraction (EF) from the myocardial performance index (MPI or Tei-index) in patients with acute myocardial infarction (MI). METHODS: Sixty-one patients in sinus rhythm without overt heart failure were examined between 2 and 7 days after the acute MI. Doppler tracings from mitral inflow and left ventricular outflow were recorded together with two-dimensional echocardiographic (2DE) recordings. MPI was calculated from the Doppler tracings, and EF measured with the biplane Simpson's method. From MPI the EF was calculated by the formula EF = 0.60 - (0.34 x MPI). Radionuclide angiographic (RNA) measurements of EF were performed within 1 day of the Doppler echocardiography. RESULTS: Compared with radionuclide EF, MPI derived EF significantly underestimated EF by 0.03 (+/-0.013; P = 0.027), whereas there was no significant difference in mean EF between 2DE and RNA. There was no statistically significant difference in the agreement between MPI derived EF relative to RNA, or 2DE relative to RNA. The agreement between the three methods was only moderate with wide limits of agreement (+/-0.17). The relationship expressed by the proposed formula for calculating EF from MPI was not statistically significant in regression analysis in this patient population. CONCLUSIONS: No statistically significant relationship was found between MPI and EF by radionuclide angiography. However, MPI derived EF was as accurate as biplane echocardiographic measurements of EF when compared with radionuclide EF, but the agreement between methods was only moderate.