Thallium-201 Myocardial Scintigraphy Research Articles

Abstract 14023: Myocardial Perfusion Abnormalities: A Potential Biomarker for Ventricular Arrhythmias in Hypertrophic Cardiomyopathy Young Patients?

Introduction: Despite progress in the field, risk stratification for sudden death in patients with hypertrophic cardiomyopathy (HCM) remains challenging. Although ventricular arrhythmias (VA) account for most of these events, the mechanisms responsible for cardiac arrest in HCM are not understood. Hypothesis: Abnormalities in myocardial perfusion may create an arrhythmogenic substrate in HCM patients. Methods/ Results: A 12-year-old boy was admitted to our department after an out-of-hospital cardiac arrest, with documented ventricular fibrillation while running. A non-obstructive asymmetric HCM was diagnosed with echocardiography (max LV wall thickness 32 mm). He had one conventional risk factor for SCD. Genetic testing revealed a heterozygous state for a MYH7 variation: p.Glu500Ala (NM_000257.3:c.1499A>C). This variation was classified as “probably pathogenic” (class 4 according to ACMG). His father and his 15-year-old brother were heterozygous for the same variant and were asymptomatic. The brother displayed a similar HCM phenotype. The patient received an implantable defibrillator and suffered from appropriate exercise-related shocks within 6-months despite sotalol therapy (160 mg bid). Because the VA occurred always when the patient was engaged in vigorous physical activity despite beta blocker and since he could not refrain from physical activity, thallium-201 myocardial scintigraphy was performed. To further understand the arrhythmogenic phenotype, his brother underwent the same investigation. Significant uptake perfusion defects in both initial and delayed images were evident in the proband (15%) but not in the asymptomatic brother. Treatment with antianginal drug (amlodipine 5 mg/day) was initiated. With 10 mg/day amlodipine was associated with a significant improvement of the scintigraphy (6% versus 15% perfusion defect). At a follow-up of 12 months, there was no recurrence of VA. Conclusions: Regarding HCM patients, the present report 1) strengthens the hypothesis that myocardial perfusion defects may identify patients at risk for VA, 2) suggests that tailored anti-ischemic prescription may be useful, and 3) underscores the need of prospective studies quantifying ischemia in HCM patients with exercise-induced VF.

Predicting the clinical course in hypertrophic cardiomyopathy using thallium-201 myocardial scintigraphy.

AimsThis study aimed to evaluate the changes in left ventricular remodelling with time in patients with hypertrophic cardiomyopathy (HCM) using thallium‐201 myocardial scintigraphy.Methods and resultsForty‐eight patients with HCM participated in the study. The extent score (ES) and a newly devised index termed the ‘mean count change’ (MCC) were used to evaluate the myocardial perfusion defects. Using the amount of thallium‐201 uptake (TU), MCC (%) was calculated using the following formula: (last TU − initial TU)∕initial TU × 100. To confirm the site of the lesion, the left ventricle was divided into five segments: anterior, septal, inferior, lateral, and apex. Cardiovascular complications and deaths were recorded. The mean follow‐up period was 8.6 ± 2.0 years. ES increased from 17.4 ± 13.7% to 44.0 ± 22.3% (P < 0.0001). MCC increased from 0% to 12.0 ± 9.0% (P < 0.0001). The apex was the most frequent site of lesion. Twenty‐seven patients (56.3%) had experienced left ventricular heart failure (LVHF). Both ES and MCC were greater in patients with LVHF than in those without LVHF. An overlap between the two groups was greater in ES than in MCC. Patients with LVHF had a higher incidence of atrial fibrillation and apoplexy. Nineteen patients (39.6%) died during the study period; 14 died from LVHF, 3 from sudden cardiac death, and 2 from cancer.ConclusionsThallium‐201 myocardial scintigraphy is useful for detecting the severity of myocardial damage and for confirming the lesion site in patients with HCM. MCC may be superior to ES in the evaluation of these changes with time.

O24-1 - Adenosine Thallium-201 Myocardial Perfusion Scintigraphy in Acute Congestive Heart Failure with Preserved Left Ventricular Ejection Fraction

O24-1 - Adenosine Thallium-201 Myocardial Perfusion Scintigraphy in Acute Congestive Heart Failure with Preserved Left Ventricular Ejection Fraction

A case of Werner's syndrome with cardiac syndrome X and heart failure with preserved ejection fraction

We herein report a case of Werner's syndrome (WS) with cardiac syndrome X (CSX) and heart failure with preserved ejection fraction (HFpEF), receiving nicorandil treatment.A 58-year-old woman with chest discomfort on exercise was suspected of having effort-angina pectoris because of broad ST-depression in electrocardiogram of exercise test and reversible defect in the posterior-wall portion of left ventricle in exercise thallium201 myocardial scintigraphy. This patient also exhibited HFpEF, diagnosed by increased ratio of early-transmitral-flow-velocity to tissue-Doppler early-diastolic mitral annular velocity (E/e′) in echocardiography and plasma B-type natriuretic peptide (BNP) levels. However, coronary angiography revealed no organic stenosis in epicardial coronary arteries, and coronary physiological measurements by PressureWire™ (St. Jude Medical, St Paul, MN, USA) demonstrated that coronary flow reserve (CFR) was greatly decreased. Because impaired CFR represents coronary microvascular dysfunction in the absence of obstructive coronary narrowing, we diagnosed CSX, and initiated the administration of nicorandil to improve coronary microcirculation. After three-month-treatment of nicorandil, the patient's symptoms were diminished, and reversible defect in exercise myocardial scintigraphy was improved. Furthermore, both E/e′ and BNP were decreased, indicating the improvement of HFpEF via the restoration of microvascular dysfunction.Thus, nicorandil administration could bring beneficial effects in WS with CSX and HFpEF, accompanied by coronary microcirculation dysfunction.<Learning objective: Contrary to previous case reports regarding Werner's syndrome (WS) with obstructive coronary artery disease (CAD), we herein report a case of WS with cardiac syndrome X (CSX) without obstructive CAD, complicated with heart failure with preserved ejection fraction (HFpEF). Because impaired coronary microcirculation is known to be associated with left ventricular hypertrophy and HFpEF, nicorandil could improve not only CSX but HFpEF via the restoration of coronary microvascular dysfunction.>

Myocardial perfusion defects in patients with chronic hepatitis B infection

The association between hepatitis B virus (HBV) infection and myocardial injury has yet to be elucidated. We sought to investigate myocardial conditions in patients with chronic HBV infection. In 47 consecutive patients with chronic hepatitis B who had no overt heart disease, we performed electrocardiography, echocardiography, serum tests for myocardial injury, and thallium-201 myocardial scintigraphy. Myocardial perfusion defects were confirmed by the severity score (SS), which was calculated as the sum of thallium-201 perfusion defect scores. The SS was followed before and after interferon (IFN) therapy in 10 patients. Abnormal ECGs were found in 9% of patients with chronic hepatitis B. SS values in the hepatitis group were significantly higher than in the control group (P < 0.0001). Abnormal SS values were found in 47% of the chronic hepatitis B patients. Independent factors related to higher pretreatment SS were serum HBV DNA titer and IgG level. After interferon (IFN) therapy, the SS values of responders were significantly reduced (P ≤ 0.02); SS values of nonresponders were not significantly different before and after IFN therapy. SS values altered following IFN therapy, along with serum IgG concentrations. Myocardial perfusion defects were found in 47% of the patients with chronic hepatitis B and improved along with HBV reduction with IFN administration. SS improvement was closely correlated with decreases in serum IgG levels.

Myocardial Perfusion Imaging in Takayasu Arteritis

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. 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. 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. 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.

Validity of automatic function imaging to measure peak systolic strain for detection of myocardial viability as compared with Thalium MPI

Thallium201 myocardial perfusion scintigraphy (MPI) is the most common modality used myocardial viability (MV), automatic function imaging (AFI) to measure peak systolic strain is relatively recent Echocardiographic modality with questionable validity for detection of viability. To evaluated the validity of peak systolic strain for detection of MV as compared with Thallium MPI. Methods: 50 patients with myocardial infarction will be included in our prospective study. Thallium MPI to be used as reference for MV (Rest-4 h and if necessary 24 h protocol). The automatically generated Bulls eye image will be used for quantitative segmental analysis and to be compared with Echocardiographic AFI for peak systolic strain with the 17 segments model of analysis (GE system). The results will be compared as segment by segment as well as regional (as per coronary territory). We present the result of first 10 case series (including analysis of 170 segments). There is over all concordance between the automated count at image of peak systolic strain and the percent of radiotracer uptake at Thallium 201 bulls eye images in both infracted and non infracted segments. The cut value of AFI for viability requires larger sample analysis. There is observed false negative results at segments with very low peak systolic strain as low as-2 that showed mild perfusion defect at rest and complete reuptake at redistribution image. Peak systolic strain is useful modality for assessment of viability, its sensitivity might be limited with false negative results compared with Thallium 201 scintigraphy.

038: In type 2 diabetic patients at goal for LDL-cholesterol, atherogenic dyslipidemia is associated with an increased risk of asymptomatic coronary artery disease

To investigate whether elevated triglycerides and low high-density lipoprotein (HDL) cholesterol (atherogenic dyslipidemia) are predictive of risk for silent myocardial ischemia (SMI) or angiographic coronary artery disease (CAD) in asymptomatic patients with type 2 diabetes. Cohort study in 1080 asymptomatic patients with type 2 diabetes, a normal 12-lead resting electrocardiogram (ECG), at least one additional cardiovascular risk factor and low density lipoprotein (LDL) cholesterol <3.4 mmol/L. Patients initially underwent screening for SMI by 201 thallium myocardial scintigraphy after an ECG stress test, a pharmacological stress test (dipyridamole injection), or both. Patients with SMI underwent coronary angiography. SMI was detected in 292 patients and CAD in 91 patients. Overall, 60 (5.5%) patients had atherogenic dyslipidemia (triglycerides ≥2.04 g/l mmol/L and HDL cholesterol ≤0,34 g/l), which was associated with SMI (40.0 vs 26.3%, p<0.001) and CAD (22.2 vs 8.3%, p<0.001). In multivariate analyses taking into account the parameters associated in univariate analyses with SMI and then CAD, SMI was associated with atherogenic dyslipidemia (odds ratio 1.8[1.0–3.3]), male gender (OR 2.1[1.5–2.9]), BMI (OR 0.97[0.94–1.00]), retinopathy (OR 1.4[1.1–1.9]), peripheral occlusive arterial disease (POAD: OR 2.5[1.6–3.8]) and mean blood pressure (OR 1.01[1.00–1.03]); CAD was associated with atherogenic dyslipidemia (OR 4.0[1.7–9.2]), male gender (OR 3.0[1.6–5.6]), BMI (OR 0.94[0.90–1.00]), retinopathy (OR 1.7[1.0–2.9], POAD (OR 4.0[2.1–7.4]) and mean blood pressure (OR 1.03[1.01–1.05]). In the subgroup of 584 patients at LDL cholesterol <2.6 mmol/L, CAD was also independently associated with atherogenic dyslipidemia (2.96 [0.97–9.03], p=0.06). In type 2 diabetic patients including those at LDL cholesterol goal, atherogenic dyslipidemia is associated with an increased risk of silent CAD. Management targeted to this dyslipidemic profile may help to reduce the high residual burden of cardiovascular disease.

Focus

Focus

Myocardial injury in patients with chronic hepatitis C infection

The existence of a direct pathogenic link between hepatitis C virus (HCV) infection and myocardial injury has not been confirmed. We investigated the association between myocardial conditions and HCV in patients with HCV-related chronic hepatitis using thallium-201 myocardial scintigraphy. In 217 consecutive cases of chronic HCV infection without overt heart disease, we performed electrocardiography (ECG), echocardiography, serum tests on myocardial injury and thallium-201 myocardial scintigraphy. Myocardial injury was confirmed by severity score (SS), which was calculated as the sum of thallium-201 perfusion defect scores. SS was followed prior to and after interferon (IFN) therapy in 200 patients with chronic hepatitis C. An abnormal ECG was found in 9% of the patients with chronic hepatitis C. Abnormal SS was found in 87% of the chronic hepatitis C patients. Independent factors related to higher pretreatment SS were histology activity index score, serum HCV RNA titer, and indocyanine green disappearance rate. After IFN therapy, SS was improved in patients with sustained virologic response. Among relapsers, SS improved at the initial disappearance of HCV RNA, but it worsened with the reappearance of HCV RNA. SS in non-viral responders did not change with IFN therapy. Myocardial perfusion defects were found in 87% of the patients with chronic hepatitis C and improved with viral eradication with IFN therapy.

Repeated sauna therapy improves myocardial perfusion in patients with chronically occluded coronary artery-related ischemia

BackgroundRepeated low-temperature sauna (Waon) therapy relieves ischemic symptoms in patients with peripheral arterial disease. We investigated whether Waon therapy could improve myocardial perfusion in patients with ischemia related to chronic total occlusion (CTO) of coronary arteries. MethodsTwenty-four patients who had ischemia in the CTO-related area were examined. The severity of ischemia was quantified by thallium-201 myocardial perfusion scintigraphy with adenosine. The Waon group (n=16) was treated daily for three weeks with a 60°C far infrared-ray dry sauna bath for 15min and then kept in a bed covered with blankets for 30min. The control group (n=8) underwent myocardial perfusion scintigraphy twice with a three-week interval. ResultsIn the control group, neither summed stress score (SSS) nor summed difference score (SDS) of myocardial scintigraphy changed. However, Waon therapy improved both SSS (16±7 to 9±6, p<0.01) and SDS (7±4 to 3±2, p<0.01), and the improvement was greater in patients with higher SSS and SDS scores at the baseline. Waon therapy extended treadmill exercise time (430±185 to 511±192s, p<0.01) and improved flow-mediated dilation of the brachial artery (4.1±1.3 to 5.9±1.8%, p<0.05), but tended to decrease the number of circulating CD34-positive bone marrow-derived cells. ConclusionsWaon therapy improves CTO-related myocardial ischemia in association with improvement of vascular endothelial function. This therapy could be a complementary and alternative tool in patients with severe coronary lesions not suitable for coronary intervention.

Effects of exercise training started within 2 weeks after acute myocardial infarction on myocardial perfusion and left ventricular function: a gated SPECT imaging study

Several studies suggested that exercise training might improve myocardial perfusion by inducing coronary vascular adaptations or enhancing collateralization. However, these findings were obtained in patients with chronic coronary artery disease using thallium-201 myocardial perfusion scintigraphy. We evaluated whether a long-term exercise-based cardiac rehabilitation (CR) started early (9 ± 3 days) after ST elevation acute myocardial infarction (STEMI) improves myocardial perfusion and left ventricular (LV) function, evaluated by gated single-photon emission computed tomography (SPECT) imaging. Randomized controlled study. Fifty patients with recent STEMI were randomized into two groups: 24 enrolled in a 6-month exercise-based CR programme (group T) and 26 discharged with generic instructions for maintaining physical activity and correct lifestyle (group C). All patients underwent cardiopulmonary exercise test and gated SPECT within 3 weeks after STEMI and at 6-month follow up. At follow up, group T showed a significant reduction of stress-induced ischaemia (p < 0.01) and an improvement in resting and post-stress wall motion (both p < 0.005) and resting (p < 0.05) and post-stress wall thickness (p < 0.005) score indexes. At follow up, group T showed an improvement in peak oxygen consumption (p < 0.0001), O(2) pulse (p < 0.05), and in the slope of increase in ventilation over carbon dioxide output (p < 0.001). No changes in myocardial perfusion parameters, LV function, and cardiopulmonary indexes were observed in group C at follow up. Six months of exercise training early after STEMI reduces stress-induced ischaemia and improves LV wall motion and thickness. Exercise-induced changes in myocardial perfusion and function were associated with the absence of unfavourable LV remodelling and with the improvement of cardiovascular functional capacity.

Non-invasive Evaluation of Internal Thoracic Artery Anastomosed to the Left Anterior Descending Artery with 320-Detector Row Computed Tomography and Adenosine Thallium-201 Myocardial Perfusion Scintigraphy

We evaluated the relationship between internal thoracic artery (ITA) stenosis anastomosed to the left anterior descending artery (LAD) and the degree of LAD stenosis using 320-detector row computed tomography (320-ADCT) and adenosine thallium-201 myocardial perfusion scintigraphy (Tl-201-MPS). We included 101 patients who underwent coronary artery bypass grafting (CABG) using ITA grafts; 320-ADCT and adenosine Tl-201-MPS were performed 2-3 months after CABG. Clinical parameters, degree of LAD stenosis, and regional myocardial ischemia of the LAD territory were compared between patients without ITA stenosis (Group A) and with ITA stenosis (Group B). Thirty patients (30%) had ≤75% LAD stenosis, and 9 patients (30%) showed significant ITA stenosis. Regional ischemia was noted in 23 patients (23%). There were no differences in clinical parameters between the 2 groups. Twenty-two patients (24%) in Group A and 8 patients (89%) in Group B had ≤75% LAD stenosis (P <0.002). No Group B patients had regional myocardial ischemia of the LAD territory. We concluded that ≤75% LAD stenosis significantly influences ITA stenosis, without associated regional myocardial ischemia of the LAD territory. Non-invasive 320-ADCT and adenosine Tl-201-MPS for ITA evaluation may be useful for long-term follow-up of patients after CABG.

Exercise-Induced Myocardial Ischemia in a Case of Anomalous Origin of the Left Main Coronary Artery from the Noncoronary Sinus of Valsalva

We report a case of anomalous origin of the left main coronary artery (LCA) from the noncoronary sinus of valsalva (LCANCS) in a young healthy patient who presented with syncope and cardiopulmonary arrest during exercise. The enhanced computed tomography showed acute angle take-off (AAT) of LCA, and the exercise stress thallium-201 myocardial scintigraphy demonstrated a large defect at the LCA perfusion region. We propose that the coexistence of AAT and resulting ischemia causes sudden cardiac death during exercise in the patients with LCANCS.

Valor pronóstico de la gammagrafía de perfusión miocárdica con 201Tl normal en el postinfarto agudo de miocardio

Objective The purpose of this work has been to determine the prognostic value of normal thallium-201 myocardial perfusion scintigraphy (MPS) in patients who had suffered myocardial infarction in the three months prior to the examination. Material and methods A stress test followed by 201Tl Gated SPECT was performed. A follow-up was made of 63 patients with normal perfusion scintigraphy. According to the MPS results, the patients were divided into 2 groups. Group I (n = 63; 57% males, age 65 ± 12), patients with normal MPS, and group II (n = 60; 81% males, age 64 ± 10), patients with abnormal MPS. The appearance of a new infarction or cardiac death occurring during this period (63 ± 3 months) was analyzed. The appearance of events was related with the cardiovascular risk factors, perfusion study and ventricular function. Results Five events occurred in group I in 4 patients: 3 new infarctions and 2 cardiac deaths. In group II, there were 18 events in 14 patients: 8 new infarctions and 10 cardiac deaths (p < 0,0001). The events were related with age, time from MPS, diabetes, size of perfusion defect and post stress ventricular ejection fraction. Mean survival en group I was 108 months (103–112) and in group II 97 (88–107) (p = 0,01). Conclusion Patients with normal MPS had fewer major events than patients with abnormal MPS. The size of MPS has been related with the appearance of events. A depressed post-stress left ventricular ejection fraction has a poor prognosis.

Investigation of the mechanism of reverse redistribution in thallium-201 myocardial perfusion scintigraphy in patients with suspicion for coronary artery spasm

BackgroundReverse redistribution (RR) is one of the features on myocardial perfusion scintigraphy (MPS) in patients with coronary artery spasm (CAS). This study was aimed to explore the mechanism of RR in patients with suspicion for CAS. Methods and ResultsThirty patients with RR and suspicion for CAS but without coronary artery stenosis (RR group) and 32 control patients without RR (control group) underwent coronary angiography before and after a dipyridamole administration. Coronary blood flow velocity and myocardial perfusion, as determined by corrected thrombolysis in myocardial infarction (TIMI) frame count (CTFC) and TIMI myocardial perfusion grade (TMPG), were measured. Coronary angiography showed significantly slower blood flow velocity [CTFC (37 ± 6) frame vs (29 ± 7) frame, P < .01] and lower myocardial perfusion [TMPG (2.08 ± 0.38) grade vs (2.55 ± 0.33) grade, P < .05] in RR-related arteries than in RR-unrelated arteries in the RR group. But, there was no significant difference among different coronary artery branches in the control group. After the injection of dipyridamole, CTFC decreased and TMPG increased in the RR group. The decline in CTFC and the increase in TMPG in RR-related arteries were more significant than those in RR-unrelated ones (28% vs 14% and 45% vs 16%, respectively; both P < .01). The endothelin-1/nitric oxide (NO) ratio was significantly higher in the RR group than in the control group before the injection of dipyridamole (2.79 ± 0.37 vs 1.70 ± 0.19, P < .01). After the injection of dipyridamole, the ratio went down in both groups, but the decline was statistically significant in the RR group (2.42 ± 0.33, P < .05) but not in the control group (1.42 ± 0.19, P < .05). Pearson correlation analysis showed that there was a positive correlation between summed rest scores on MPS and the endothelin-1/NO ratio (r = 0.853, P = .000) as well as CTFC (r = 0.808, P = .000) before the injection of dipyridamole in the RR group. ConclusionPatients with suspicion for CAS may exhibit a mild spasm of RR-related arteries and corresponding microvasculature and a significant imbalance of coronary blood flow velocity and myocardial perfusion at rest between RR-related and RR-unrelated areas. This is overcome by stress-induced hyperemic flow increases and which may account for RR on MPS.

The role of metamizol induction for the detection of perfusion reversibility on thallium-201 myocardial perfusion scintigraphy

Metamizol, probably with its vascular smooth muscle relaxant effect, enhances rest myocardial perfusion with the use of technetium-99m-methoxyisobutylisonitrile. We aimed to investigate whether metamizol induction is also able to increase the detectability of the ischemic/jeopardized myocardium during thallium-201 myocardial perfusion scintigraphy (MPS). Twenty patients who had partially reversible/irreversible perfusion defects on their routine stress-redistribution-reinjection thallium-201 MPS were enrolled and metamizol-induced thallium-201 MPS (111 MBq thallium-201 was injected 45 min after 1 g oral metamizol) was acquired (10 min, 1 and 3 h later). Routine MPS and metamizol-induced MPS images were interpreted on the model of 17 segments using a visual uptake score (VUS; 0=normal, 1=mild, 2=moderate, 3=significant decreases, 4=no uptake). Thallium-201 uptake ratios (mean counts in the region of the perfusion defect/mean counts in the region of the normal-perfused wall) were calculated for each MPS. Blood pressure was monitored at 15-min intervals. MPS were compared with coronary angiography results. Visual uptake score and thallium-201 uptake ratio results indicated that in the first and third hour metamizol-induced thallium-201 uptake was significantly higher (P<0.001) than the redistribution/reinjection studies in 26 ischemic myocardial walls. Fourteen myocardial walls showed no thallium-201 uptake on either MPS and were considered as myocardial infarction. Statistically significant but asymptomatic decreases in blood pressure were observed. Coronary angiography results were in concordance with metamizol-induced MPS. Metamizol increases the detectability of ischemic/viable myocardium during MPS with thallium-201 and could be used with MPS.

Prognostic value of normal myocardial perfusion scintigraphy with 201Tl in post-acute myocardial infarction

Objective The purpose of this work has been to determine the prognostic value of normal thallium-201 myocardial perfusion scintigraphy (MPS) in patients who had suffered myocardial infarction in the three months prior to the examination. Material and methods A stress test followed by 201Tl Gated SPECT was performed. A follow-up was made of 63 patients with normal perfusion scintigraphy. According to the MPS results, the patients were divided into 2 groups. Group I (n = 63; 57% males, age 65 ± 12), patients with normal MPS, and group II (n = 60; 81% males, age 64±10), patients with abnormal MPS. The appearance of a new infarction or cardiac death occurring during this period (63±3 months) was analyzed. The appearance of events was related with the cardiovascular risk factors, perfusion study and ventricular function. Results Five events occurred in group I in 4 patients: 3 new infarctions and 2 cardiac deaths. In group II, there were 18 events in 14 patients: 8 new infarctions and 10 cardiac deaths (p<0.0001). The events were related with age, time from MPS, diabetes, size of perfusion defect and post stress ventricular ejection fraction. Mean survival en group I was 108 months (103-112) and in group II 97 (88-107) (p=0.01). Conclusion Patients with normal MPS had fewer major events than patients with abnormal MPS. The size of MPS has been related with the appearance of events. A depressed post-stress left ventricular ejection fraction has a poor prognosis.

A Case of Cardiac Sarcoidosis with Complete Atrioventricular Block Revealed by Gastric Biopsy

A 67-year old woman was emergently admitted because of fainting spells. Electrocardiography showed complete atrioventricular block, and echocardiography demonstrated reduced left ventricular systolic function. Decreased uptake was observed in multiple areas on thallium myocardial scintigraphy; however, coronary angiography showed no significant stenosis. Diffuse left ventricular hypokinesis and complete AV block strongly suggested cardiac sarcoidosis or amyloidosis, but a definitive diagnosis could not be established because histological evidence was lacking. Giant multinucleated cells were incidentally detected on gastric biopsy, and the diagnosis of sarcoidosis was made.

Discinergia ventricular esquerda reversível identificada por potenciação pós-extrassistólica em miocardiopatia chagásica crônica não é causada por hibernação miocárdica

INTRODUCAO: A alteracao regional da mobilidade segmentar do ventriculo esquerdo e marcador precoce de miocardiopatia chagasica cronica. Demonstramos recentemente que a discinergia em algumas regioes ventriculares pode ser revertida pela potenciacao pos-extrassistolica. Apesar de angiografia coronaria normal, pacientes com miocardiopatia chagasica apresentam falhas de perfusao, corroborando a hipotese de que a hibernacao miocardica pode ser responsavel pelas anormalidades de mobilidade segmentar revertidas durante a potenciacao pos-extrassistolica. METODO: Vinte e dois pacientes consecutivos portadores de miocardiopatia chagasica foram submetidos a angiografia coronaria, ventriculografia e cintilografia miocardica com talio-201 com o protocolo estresse-redistribuicao-reinjecao para avaliacao da perfusao dos segmentos do ventriculo esquerdo demonstrando potenciacao pos-extrassistolica. RESULTADOS: Nao foram observadas obstrucoes coronarias significativas nos pacientes avaliados. Potenciacao pos-extrassistolica ocorreu em pelo menos um segmento ventricular esquerdo em 14 dos 22 pacientes, sendo observada em segmentos ventriculares com diminuicao de mobilidade de moderada a intensa, mas nao em segmentos com discinesia. Esses pacientes apresentaram melhora da media da pontuacao de mobilidade segmentar de 1,49 ± 0,73 para 1,36 ± 0,76 do batimento basal ao batimento pos-extrassistolico (P < 0,05). Nessas areas, a perfusao miocardica era normal ou apenas levemente prejudicada e sem demonstracao de isquemia com exercicio ou estresse farmacologico. CONCLUSAO: Estes resultados nao corroboram a hipotese de miocardio hibernante causado por disturbio de perfusao microvascular na miocardiopatia chagasica.