Biomedical subjects

Shinichi Sumita

Publications and source records attributed to Shinichi Sumita.

At least 19 recordsLinked to original sources

PubMed2007

Reverse perfusion-metabolism mismatch predicts good prognosis in patients undergoing cardiac resynchronization therapy: a pilot study.

BACKGROUND: Cardiac resynchronization therapy (CRT) improves glucose metabolism in the septum of patients with heart failure, so in the present study the predictive value of combined fluorodeoxyglucose (FDG)-positron emission tomography (PET) and metoxy-isobutyl isonitrile (MIBI)-single photon emission computed tomography (SPECT) for the prognosis of patients undergoing CRT was investigated. METHODS AND RESULTS: Fourteen patients (70.3+/-8.2 years) who underwent FDG-PET and MIBI-SPECT before implantation of a biventricular pacemaker were enrolled. The total number of matches, mismatches, reverse mismatches, summed difference score (SDS: sum total of FDG - MIBI scores) and SDS per segment (%SDS) in each of 5 areas of myocardium (septum, anterior, lateral, inferior area, apex) was calculated and compared between the survival groups (all survival: survival group; survival without ischemic heart disease (IHD): non-IHD survival group) and non-survival group. Both the number of reverse mismatch segments and the %SDS in the septum in the non-IHD survival group were significantly greater than in the non-survival group (3.2+/-1.6 vs 0.5+/-0.6, p<0.05; 0.62+/-0.61 vs -0.11+/-0.19, p<0.05). The receiver-operating characteristics curves for prognosis showed that the area under the curve for the number of reverse mismatch segments in the septum (0.93; confidence interval 0.61-0.98) was significantly greater. CONCLUSION: A reverse mismatch pattern in the septum can predict a good prognosis for patients treated with CRT.

Aged↗

PubMed2006

Evaluation of myocardial glucose metabolism before and after recovery of myocardial function in patients with tachycardia-induced cardiomyopathy.

BACKGROUND: We assessed left ventricular (LV) function and myocardial glucose metabolism by fluoro-18-deoxyglucose (18F-FDG) positron emission tomography (PET) in patients with tachycardia-induced cardiomyopathy (TC). METHODS: The subjects were 42 patients with heart disease, consisting of 7 patients with TC (61.4 +/- 19.0 years, LVEF 34.1%+/- 10.6%) and 35 with ischemic heart disease (IHD) (63.1 +/- 10.8 years, LVEF 49.9%+/- 13.5%). Five volunteers with normal ECG were the control group. All of the patients underwent 18F-FDG PET and echocardiography, and all of the patients with TC underwent 18F-FDG PET and echocardiography before and 6 months after antitachycardia therapy. Six patients underwent radiofrequency catheter ablation (RFCA) and 1 patient was medically treated with antitachycardia therapy. Myocardial glucose metabolism was assessed semiquantitatively by using the % dose uptake of 60 kg of BW (% dose uptake). RESULTS: Mean % dose uptake of the control group was 5.52 +/- 0.54%. After antitachycardia therapy, LVEF significantly improved (34.1 +/- 10.6% vs 54.3 +/- 13.6%, P < 0.01), and % dose uptake also significantly improved (1.26 +/- 0.55% vs 1.49 +/- 0.62%, P < 0.05). Patients with IHD showed higher % dose uptake than those with TC before antitachycardia therapy (3.18 +/- 1.36 vs 1.26 +/- 0.55%, P < 0.01), controls showed higher value of % dose uptake than TC before antitachycardia therapy (5.52 +/- 0.54% vs 1.26 +/- 0.55%, P < 0.01). CONCLUSION: Semiquantitative analysis of 18F-FDG PET showed that antitachycardia therapy improved myocardial glucose metabolism in patients with TC.

Cardiomyopathies↗

PubMed2006

Assessment of atrial regional wall motion using strain Doppler imaging during biatrial pacing in the bradycardia-tachycardia syndrome.

INTRODUCTION: Biatrial pacing is expected to have preventive effects on atrial fibrillation. METHODS: We evaluated atrial regional wall motion by strain Doppler imaging (SDI) in 6 patients (62.5 +/- 11.3 [SD] years), who suffered from atrial fibrillation, with an implanted biatrial pacemaker. SDI was performed and atrial regional wall motion was estimated during biatrial (BiA) and right atrial appendage (RAA) pacing. RESULTS: There was no significant difference in the interval from the pacing spike to the peak strain of the atrium in the lateral right atrium (LRA) between BiA and RAA pacing. However, there was a significant difference in the septal atrium (SA) between BiA and RAA pacing (225.0 +/- 19.9 vs 267.2 +/- 15.7 ms, P < 0.0001) and in the lateral left atrium (LLA) between BiA and RAA pacing (216.7 +/- 21.6 vs 275.0 +/- 16.2 ms, P < 0.0001). There were significant differences in the time difference of peak strain between BiA and RAA pacing in each atrial segment (LRA-AS: 2.2 +/- 5.9 vs 45.0 +/- 11.9 ms, P = 0.0016, SA-LLA: -8.3 +/- 5.5 vs 7.8 +/- 2.7 ms, P < 0.0011, LRA-LLA: -6.1 +/- 3.9 vs 52.8 +/- 13.2 ms, P = 0.0002). There was no significant difference in the interval from the pacing spike to the inflection point of atrial strain (S-I) of LRA. However, there were significant differences in S-I of SA (83.9 +/- 24.1 vs 129.9 +/- 30.6 ms, P = 0.0086) and LLA (102.2 +/- 37.9 vs 166.1 +/- 13.4 ms, P = 0.0028). CONCLUSION: BiA pacing improved the synchronicity of regional wall motion of both atrium.

Adult↗

PubMed2006

Suppression of atrial fibrillation by atrial pacing.

BACKGROUND: Atrial fibrillation (AF) is a common arrhythmia in patients with an implanted pacemaker, but the role of atrial pacing in preventing AF is still unclear. METHODS AND RESULTS: Sixty-six patients (67.8+/-12.1 years) were enrolled: 54 with sick sinus syndrome (SSS), 11 with atrioventricular blocks (AVB), and 1 with SSS and AVB. The prevalence of AF was investigated. In 22 patients with AF, the AF burden was estimated under "back-up pacing" (40-50 beats/min), then under "atrial pacing" (60-85 beats/min). The prevalence of AF in the SSS group tended to be higher than that in the AVB group (48.1% vs 18.2%, p=0.06). The AF burden in patients with a percentage of atrial pacing (% atrial pacing) <50% was significantly greater than that in patients with % atrial pacing >or=50% (12.5+/-21.1% vs 4.2+/-10.3%, p<0.05). AF disappeared immediately after "atrial pacing" in 4 patients (18.2%). In 9 patients (40.9%), the AF burden decreased gradually, and AF disappeared in 6 patients (27.3%) after 207.9+/-130.2 days. CONCLUSION: The prevalence of AF may be higher in patients with SSS than in those with AVB. Atrial pacing has a preventive effect on AF, and the effect of atrial pacing is not always immediate but is progressive in some patients.

Aged↗

PubMed2006

Daily shock impedance measured by implantable cardioverter defibrillator is useful in the management of congestive heart failure.

BACKGROUND: Clinical data suggest that changes in intrathoracic impedance and fluid accumulation in the lung are inversely related. METHODS AND RESULTS: Daily shock impedance (S-IMP) was evaluated in 29 patients in whom a Ventak Prizm 2 was implanted (61+/-14 years old). The mean follow-up period was 45+/-18 weeks, during which 6 patients had episodes of decompensated heart failure (DHF group) and the others did not (NHF group). There was no significant difference between the DHF group and NHF group in the mean value of the S-IMP (46.4 +/-3.3 vs 45.4+/-5.4 Omega). The range of S-IMP in individual patients in the DHF group was significantly greater than that in the NHF group (13.8+/-0.38 vs 7.0+/-3.1 Omega, p<0.0001). Mean weekly change of S-IMP in individual patients in the DHF group was significantly greater than that in the NHF group (1.583+/-0.630 vs 1.092+/-0.361 Omega, p<0.0176). When the cut-off value was set at >1.242 Omega, sensitivity was 100% and specificity was 69.6% for a diagnosis of DHF. There was a significant negative correlation between the percent increases in brain natriuretic peptide (BNP) and S-IMP (correlation coefficient: -0.775 p<0.0001) in the DHF group. There was an inverse relation between BNP and S-IMP. CONCLUSIONS: Measurement of shock impedance may be useful in the management of congestive heart failure.

Aged↗

PubMed2006

Comparison of nifekalant and lidocaine for the treatment of shock-refractory ventricular fibrillation.

BACKGROUND: Although nifekalant is a class III antiarrhythmic agent without negative inotropic activity, its effect in patients with shock-refractory ventricular fibrillation remains unclear. METHODS AND RESULTS: Patients who had an out-of-hospital cardiac arrest with ventricular fibrillation that persisted after 3 shocks from an external defibrillator, intravenous epinephrine, and another shock were retrospectively studied. The patients received lidocaine from January 1997 through June 2001 and nifekalant from July 2001 through December 2004. Short-term survival rates (survival to hospital admission and 24-h survival) were compared between the groups. The study group comprised 120 patients (mean age: 62+/-16 years): 55 received nifekalant and 65 received lidocaine. Age, sex, history of ischemic heart disease, whether arrest was witnessed or not and time to arrival at the hospital did not differ significantly between the groups. As compared with lidocaine, nifekalant was associated with significantly higher rates of survival to hospital admission (67% vs 37%, p<0.001) and 24-h survival (53% vs 31%, p=0.01). Multivariate analysis showed that treatment with nifekalant and early initiation of cardiopulmonary resuscitation were independent predictors of 24-h survival. CONCLUSIONS: As compared with lidocaine, nifekalant may improve short-term survival in patients with out-of-hospital cardiac arrest due to shock-refractory ventricular fibrillation.

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PubMed2006

[Improvement of central sleep disordered breathing with severe congestive heart failure by biventricular pacing therapy: a case report].

A 74-year-old man with ischemic cardiomyopathy was repeatedly admitted for congestive heart failure. His left ventricular ejection fraction was 21% and diastolic left ventricular dimension was 73.5mm by echocardiography. He was treated with biventricular pacing and heart failure improved from New York Heart Association class III to II. Before the treatment, brain natriuretic peptide was 600.5 pg/ml. Apnea hypopnea index was 23.8 and all events were central type. After biventricular pacing, apnea hypopnea index was improved to 21.9 after 11 days, 14.0 after 33 days, and 4.8 after 48 days. His left ventricular ejection fraction was 36%, diastolic left ventricular dimension was 71.4mm, and brain natriuretic peptide was 383.8 pg/ml. In this patient, central sleep disordered breathing was improved by biventricular pacing therapy after only 48 days.

Aged↗

PubMed2005

Long-term follow-up of atrioventricular delay optimization in patients with biventricular pacing.

BACKGROUND: Atrioventricular (AV) delay optimization may be important in patients with biventricular pacing and the optimal AV delay can be predicted using Doppler echocardiography and the formula: optimal AV delay = AV delay-the interval between the end of A wave and complete closure of the mitral valve when the AV delay is set at slightly prolonged AV delay. METHODS AND RESULTS: In the present study the efficacy of this method was evaluated in 5 patients (67.4+/-8.0 (SD) years old) with biventricular pacing. Cardiac output (CO) and diastolic filling time were measured by Doppler echocardiography. When the AV delay was set at the predicted optimal AV delay -25 ms, the predicted optimal AV delay (133+/-66 ms) and predicted optimal AV delay + 25 ms, the respective CO were 4.5+/-0.9, 5.3+/-1.0, 4.8+/-1.0 L/min (p<0.05, ANOVA) and the diastolic filling times were 364 +/-100, 373+/-105, 335+/-84 ms (p<0.05, ANOVA). Congestive heart failure improved from New York Heart Association class 3.6+/-0.5 to 1.4+/-0.5 (p<0.001). CONCLUSIONS: AV delay optimization is important in patients with biventricular pacing and can be easily achieved by the new method.

Aged↗

PubMed2005

Beneficial effects of biatrial pacing on cardiac function in patients with bradycardia -- tachycardia syndrome.

BACKGROUND: Biatrial (BiA) pacing prevents atrial fibrillation. By an unknown mechanism. The purpose of this study was to use Doppler echocardiography to evaluate the hemodynamic effects during BiA pacing. METHODS AND RESULTS: The subjects were 7 patients with bradycardia - tachycardia syndrome with an implanted pacemaker. Atrial pacing sites were the right atrial appendage (RAA) and coronary sinus. P wave duration during BiA pacing (123 +/-16 ms) was significantly shorter than during either RAA pacing (167+/-19 ms, p<0.05) or sinus rhythm (148+/-12 ms, p<0.05). Doppler echocardiography revealed a greater cardiac output during BiA pacing than during RAA pacing (4.1+/-1.1 vs 3.5+/-0.7 L/min, p=0.042). The Doppler waveform of transmitral flow indicated that the left ventricular contraction interrupted the atrial filling wave during RAA pacing. The interval between the end of the atrial filling wave of transmitral flow and the mitral valvular closing sound was significantly increased by BiA pacing compared with RAA pacing (56+/-65 vs 40+/-57 ms, p=0.047). CONCLUSION: Cardiac hemodynamics were improved by BiA pacing and reduction of left atrial load may be one of the mechanisms.

Aged↗

PubMed2005

[Successful defibrillation by disconnection of superior vena cava electrode for high defibrillation threshold: a case report].

A 72-year-old man with dilated cardiomyopathy and sustained ventricular tachycardia was treated with amiodarone. He visited another hospital because of loss of consciousness. Electrocardiography showed 2: 1 atrioventricular block. Ambulatory electrocardiography showed total heart beats were 59,700 per day. He was referred to our hospital to evaluate his heart. Several types of ventricular tachycardia and ventricular fibrillation were induced by program stimulation during the electrophysiological study. Therefore, an implantable cardioverter-defibrillator was introduced. During defibrillation threshold tests, ventricular fibrillation could not be terminated by the maximal output of 31J. Despite changing the polarity and lead position, stable defibrillation could not be obtained. Finally, successful defibrillation could only be achieved by disconnection of the superior vena cava electrode.

Aged↗

PubMed2005

[Neurally mediated syncope with significant cardiac arrest and asymptomatic multiple cerebral infarctions: a case report].

A 32-year-old man had suffered episodes of loss of consciousness since childhood. He was admitted to another hospital because of three syncopal episodes in one day. He was referred to our hospital because of asymptomatic multiple lacunae indicating cerebral infarction on magnetic resonance imaging. He lost consciousness with convulsion followed by a 70-second interval of cardiac arrest during blood sampling. He reported the onset of his usual prodromal symptoms after 1 min in the 80 degrees head-up tilt position. He lost consciousness 2 min after returning to the supine position. Electrocardiography demonstrated a 10-second interval of cardiac arrest. Magnetic resonance angiography, carotid arterial echography, brain perfusion scintigraphy, and laboratory chemistry and hematology examinations identified no significant findings. Cerebral infarction had occurred in watershed areas, so hemodynamic change during cardiac arrest may be the main cause of the infarctions. He suffered no further syncopal or presyncopal episodes after implantation of a DDD pacing system.

Adult↗

PubMed2004

Clinical usefulness of ECG-gated 18F-FDG PET combined with 99mTC-MIBI gated SPECT for evaluating myocardial viability and function.

OBJECTIVES: This study sought to evaluate an imaging approach using gated 99mTc-MIBI (MIBI) SPECT and gated 18F-FDG (FDG) PET for assessment of myocardial viability and cardiac function. METHODS: Forty-eight patients (38 men, mean age 68.1 +/- 9.6 years) underwent ECG-gated FDG PET and MIBI SPECT within a week. The baseline diagnoses were coronary artery disease (31), mitral regurgitation (1), paroxysmal arrhythmia (10), and dilated cardiomyopathy (6). The gated FDG PET data were analyzed using pFAST software, and the gated MIBI SPECT data were analyzed using QGS software. Fifteen patients were diagnosed with myocardial infarction, and follow-up study was performed to assess the functional outcome four months later. An improvement in LVEF of >5% was defined as significant. The LV myocardium was divided into 17 segments, and regional defect scores were visually assessed using a 4-point scale for each segment (0 = normal, 1 = mildly reduced, 2 = moderately reduced, 3 = absent). A segment with a greater defect score on MIBI SPECT than on FDG PET was defined as a mismatch. The patients were divided into two groups: those with at least two mismatched segments (MM-group), and those with none or one (M-group). RESULTS: LVEF, EDV and ESV measured by gated FDG PET were highly correlated with those obtained by gated MIBI SPECT (r = 0.848, 0.855 and 0.911, p < 0.0001, respectively). The mean values of LVEF did not differ significantly, but EDV and ESV obtained by gated FDG PET were significantly grater than those obtained by gated MIBI SPECT (p < 0.0001). In 15 patients diagnosed with myocardial infarction, a significant association (p < 0.05) was found between the relative uptake of FDG PET and MIBI SPECT and the functional outcome 4 months later. Global LV function improved in 6 of the 8 patients showing mismatch but in only 1 of the 7 patients with matched defects, resulting in a sensitivity of 86% and specificity of 75%. The overall accuracy to predict global functional outcome was high (80%). CONCLUSION: This imaging approach allows accurate evaluation of myocardial viability. Furthermore, the high correlations of gated FDG PET and gated MIBI SPECT measurements hold promise for the assessment of left ventricular function using gated FDG PET.

Aged↗

PubMed2004

Assessment of regional wall motion by strain Doppler during biventricular pacing in patients with conventional indications for a pacemaker.

Biventricular pacing therapy is effective in patients with severe congestive heart failure. Strain Doppler imaging (SDI) is a new tool for measuring regional myocardial deformation. We evaluated regional wall motion by strain Doppler imaging in 13 patients who had conventional indications for a pacemaker (74 +/- 6 years old) and in six with NYHA Class III or IV heart failure with a biventricular pacemaker (HF-RV: during right ventricular pacing, HF-BV: during biventricular pacing). The other seven patients had normal LV function (N-RV). Wall motion was assessed by strain of the myocardium, and the interval between the Q wave of the surface ECG and the peak strain (QPSI) was measured in three septal and three lateral segments. Interventricular contraction delay was determined as the interval between the onset of the left and right ventricular outflow waves. Intraventricular contraction delay was determined as the time difference between minimum and maximum QPSI. Strain of HF-RV was significantly greater than that of N-RV (-9.6%+/- 2.5% vs -14.4%+/- 2.3%, P < 0.0001). Intraventricular contraction delay of HF-RV was significantly greater than that of N-RV (273 +/- 12 vs 151 +/- 69 ms, P = 0.0004). Strain of HF-RV was not significantly greater than that of HF-BV (-9.6% +/- 2.5% vs -10.6% +/- 2.9%). Interventricular contraction delay of HF-RV was greater than that of HF-BV (37.2 +/- 44.7 vs 16.2 +/- 47.4 ms, P < 0.0001). Intraventricular contraction delay of HF-RV was significantly greater than that of HF-BV (322 +/- 101 vs 209 +/- 88 ms, P = 0.0006). In conclusion, biventricular pacing improves both interventricular contraction delay and intraventricular contraction delay in patients with conventional indications for a pacemaker with severe congestive heart failure, and SDI is useful to predict the efficacy of biventricular pacing.

3' Flanking Region↗

PubMed2004

Double-counting of intracardiac electrogram during biatrial pacing.

BACKGROUND: Biatrial pacing has a significant problem with memory function that misinterprets normal sinus rhythm as atrial tachyarrhythmias and in addition estimation of the atrial pacing thresholds (biatrial and uniatrial pacing thresholds) is sometimes difficult because of small P waves. METHODS AND RESULTS: The intracardiac electrograms recorded by a pacemaker in 10 patients (age, 66.7+/-10.7 (SD) years) with implanted biatrial pacemakers were analyzed. Atrial sensing within the atrial refractory period after atrial pacing was counted in 6 of the 10 patients (timing of the double counting was 143+/-64 ms) when pacing failed in the left or right atrium. Atrial sensing within the atrial refractory period after atrial pacing disappeared when biatrial pacing was successfully performed. Atrial double-counts depend on interatrial conduction delay. The memory function of implanted pacemaker devices misinterpreted normal sinus rhythm as atrial tachyarrhythmias because of atrial double-counts. On the other hand, the biatrial pacing threshold was easily recognized using this phenomenon. CONCLUSIONS: The memory function of pacemaker devices is unreliable because of atrial double-counting during sinus rhythm in patients with biatrial pacing. However, the biatrial pacing threshold is easily checked using this phenomenon.

Aged↗

PubMed2004

Prevalence of right bundle-branch block and right precordial ST-segment elevation (Brugada-type electrocardiogram) in Japanese children.

BACKGROUND: The prevalence of Brugada-type electrocardiogram (ECG) in schoolchildren remains unclear. This study aimed to further investigate this condition. METHODS AND RESULTS: We studied the prevalence of Brugada-type ECG in 20,387 children (10,434 males and 9,953 females, 9.7 +/- 3.2 [SD] years old) during a school health examination in Kanagawa Prefecture, Japan, in 2002. We considered right bundle-branch block and ST-segment elevation of the J point of > or =0.1 mV in leads V1 through V3 as Brugada-like ECG, and an ECG was considered to be Brugada-type when the 12-lead ECG fully meet the criteria for the Brugada syndrome as recently published in a consensus report. Only 2 children (0.0098%, 95% confidence interval (CI): 0 to 0.023%) completely conformed to the criteria for Brugada-type ECG. Brugada-like ECG was found in 11 (10 male) of 20,387 children (0.054%, 95% CI: 0.022 to 0.086%). The prevalence in males was significantly higher than that in females, even in children (0.096% vs 0.010%, p=0.012). Stratified according to age, there was tendency for the prevalence of Brugada-like ECG to increase up to puberty (first graders, 0.01%; fourth graders, 0.05%; seventh graders, 0.08%; tenth graders, 0.23%; p=0.068). CONCLUSION: The prevalence of Brugada-type ECG in Japanese children was much lower than that reported in the adult population.

Adolescent↗

PubMed2004

Different clinical and coronary angiographic findings according to ratios of total cholesterol to high-density lipoprotein cholesterol during the acute phase of myocardial infarction.

OBJECTIVES: Several pathological studies have shown that a higher ratio of the serum total cholesterol concentration to the high-density lipoprotein cholesterol concentration (TC/HDL-C ratio) is associated with plaque rupture in patients with acute coronary syndromes. We examined the relationship between the serum total cholesterol concentration and the TC/HDL-C ratio, and clinical and angiographic findings in patients with first acute myocardial infarction. METHODS: Two hundred eighty patients were classified into quartiles according to the TC/HDL-C ratio measured within 24 hr from symptom onset: 70 patients in the first quartile (group L: mean TC/HDL-C ratio, 3.0), 140 in the second and third quartiles (group M: mean TC/HDL-C ratio, 4.6), and 70 in the fourth quartile (group H: mean TC/HDL-C ratio, 7.5). RESULTS: There were no differences among the three groups with regard to sex, diabetes mellitus or hypertension. Patients in group L were older (66 +/- 9 vs 60 +/- 11, 56 +/- 10 years, p < 0.01) and had a higher incidence of stable angina before acute myocardial infarction (26% vs 14%, 10%, p < 0.05) than in patients groups M and H. Although coronary angiograms revealed no difference in the number of diseased vessels among the three groups, extent index indicating the proportion of each coronary segment that appears angiographically abnormal was lowest in group L (0.7 +/- 0.5), followed by group M (1.3 +/- 0.6), and high- est in group H ( 1.7 +/- 0.6, p < 0.01). The number of segments with calcification and the incidence of calcification in the culprit lesion were higher in group L than in groups M and H. CONCLUSIONS: Our findings suggest that the clinical presentations and angiographic appearances differ according to the TC/HDL-C ratio in the acute phase of acute myocardial infarction.

Acute-Phase Reaction↗

PubMed2004

[Assessment of regional wall motion using strain Doppler imaging during right ventricular bifocal pacing in a patient with severe congestive heart failure: a case report].

A 79-year-old man presented with dilated cardiomyopathy and chronic atrial fibrillation. A DDD pacemaker was implanted due to sick sinus syndrome. His left ventricular ejection fraction was 23%. He was repeatedly admitted with congestive heart failure. Although cardiac resynchronization therapy was attempted, insertion of a pacing lead into the coronary sinus failed. Right ventricular bifocal pacing was done. The QRS width was shortened to 155 msec during bifocal pacing and 157 msec during right ventricular outflow pacing from 221 msec during right ventricular apical pacing. Heart failure was improved from New York Heart Association class III to II. Regional wall motion was assessed by strain of the myocardium. Bifocal pacing increased stroke volume due to improvement of longitudinal dyssynchrony of the septal and lateral walls. Bifocal pacing is effective for patients with severe congestive heart failure in whom biventricular pacing therapy has failed. Strain Doppler imaging is useful for the assessment of regional wall motion during cardiac pacing.

Aged↗

PubMed2003

Effect of biventricular pacing on myocardial glucose metabolism in patients with heart failure using fluoro-18-deoxyglucose positron emission tomography.

Biventricular pacing has recently been found beneficial in the treatment of congestive heart failure (CHF). Meanwhile, positron emission tomography (PET) has emerged as a new method to analyze glucose metabolism in the heart. Five patients (mean age 68.8 +/- 8.1 years, 4 men) who received biventricular pacing therapy for 5.8 +/- 6.6 weeks for CHF were studied. Myocardial glucose metabolism was evaluated by PET with fluoro-18-deoxyglucose (18F-FDG), and percent uptake (%uptake) of 18F-FDG was calculated during biventricular pacing and compared with that during 1 hour of conventional RV pacing. Biventricular pacing was associated with a significant decrease in NYHA functional Class from 3.67 +/- 0.52 to 2.50 +/- 0.55. After 18F-FDG PET, three of five patients remained clinically stable, and two died during follow-up. Mean 18F-FDG %uptake during biventricular pacing was not different than during short-term RV pacing (62.1 +/- 18.4 vs. 63.6 +/- 17.0%). However, patients who remained clinically stable had a lower value of 18F-FDG %uptake in the septal region than patients who died (46.9 +/- 5.6 vs 80.3 +/- 1.3%, P < 0.01). One patient whose cardiac function improved significantly also had a small septal region of decreased 18F-FDG uptake during RV pacing. In conclusion, biventricular pacing therapy was effective in this small group of patients with severe, drug-resistant CHF. An evaluation of the effects of biventricular pacing on glucose metabolism in the subacute phase may help identify patients with a favorable long-term response to this therapy.

Aged↗