Serial cardiac 123I-metaiodobenzylguanidine scintigraphic studies are more useful for predicting cardiac death than one-time scan in patients with chronic heart failure: sub-analysis of our previous report

Assessment of therapeutic effects of statin on cardiac sympathetic nerve activity and cardiac events in patients with ischemic cardiomyopathy and mild to moderate heart failure

INTRODUCTION

We determined whether statin therapy improved cardiac sympathetic nerve activity as evaluated using iodine-123-metaiodobenzylguanidine (I-MIBG) scintigraphy, and whether this therapy affects prognosis in patients with ischemic cardiomyopathy.

PATIENTS AND METHODS

This study was a subanalysis of our previous report of the result that the serial I-MIBG scintigraphic studies were the most useful prognostic indicator in patients with heart failure. Patients with heart failure [left ventricular ejection fraction (LVEF) <45%] but no cardiac events for at least 5 months before the study were identified according to their history of decompensated acute heart failure requiring hospitalization. The patients underwent I-MIBG scintigraphy and echocardiography immediately before hospital discharge and after 6 months. The % denervation, heart/mediastinum count ratio, and washout rate were determined from the I-MIBG scintigraphy, and the left ventricular end-diastolic volume, left ventricular end-systolic volume, and LVEF were also determined from echocardiography. We selected 76 patients with old myocardial infarction without active ischemia and used propensity score matching to compare patients who received oral statin (n=38) with those who did not (n=38). The patients were followed up for a median of 4.74 years, with the primary and secondary study end points defined as incidences of fatal cardiac events and major adverse cardiac events (MACEs), respectively.

RESULTS

After treatment, the I-MIBG scintigraphic and echocardiographic parameters were improved in the statin and nonstatin groups. However, the extent of change in the % denervation was -12.3±10.3 and -6.2±9.6 (P<0.01), whereas that in the heart/mediastinum count ratio was 0.19±0.14 and 0.08±0.15 (P<0.01), and that in washout rate was -8.1±7.2 and -0.5±9.2% (P<0.01). The extent of change in left ventricular end-diastolic volume, left ventricular end-systolic volume, and LVEF in the statin group tended to exceed than in the nonstatin group, but these changes were not statistically significant. Of the 76 patients, 18 experienced fatal cardiac events and 32 experienced MACEs during the study. Multivariate Cox regression analyses revealed that the nonstatin therapy was a significant predictor of both cardiac death and MACEs in our patients. On Kaplan-Meier analysis, the rates of freedom from cardiac death or MACEs were significantly higher in the statin group than those in the nonstatin group (all, P<0.05).

CONCLUSION

Statin therapy improved cardiac sympathetic nerve activity in patients with ischemic cardiomyopathy and mild to moderate heart failure. Furthermore, statin is potentially effective for reducing cardiac events in these patients.

Effects of statin therapy on cardiac sympathetic nerve activity and left ventricular remodeling in patients with chronic heart failure: a propensity score-matched analysis

Statin therapy reduces enhanced cardiac sympathetic nerve activity (CSNA) in patients with heart disease, and prevents left ventricular (LV) remodeling in chronic heart failure (CHF) patients. We sought to evaluate the effects of statin therapy on CSNA, as evaluated by I-metaiodobenzylguanidine (MIBG) scintigraphy, and LV remodeling in CHF patients. This study was sub-analysis of our previous report of the result that the serial I-MIBG studies were the most useful prognostic indicator in CHF patients. Patients with CHF (n = 208; left ventricular ejection fraction <45%) but no cardiac events for at least 5 months before the study, were identified according to their history of decompensated acute heart failure requiring hospitalization. The patients underwent I-MIBG scintigraphy and echocardiography immediately before hospital discharge and after 6 months. The delayed % denervation, delayed heart/mediastinum count (H/M) ratio, and washout rate (WR) were determined by I-MIBG scintigraphy. The LV end-diastolic volume (EDV) and end-systolic volume (ESV) were also determined by echocardiography. We selected 164 patients and used propensity score matching to compare patients who received oral statin (n = 82), and those who did not (n = 82).The changes in I-MIBG scintigraphic parameters improved, and in echocardiographic LVEDV and LVESV reduced in the statin group compared with those in the non-statin group. Moreover, there were significant correlations between changes in the I-MIBG scintigraphic findings and those in the LVEDV (% denervation, r = 0.534, P < 0.001; H/M ratio, r =  -0.516, P < 0.001; and WR, r = 0.558, P < 0.001); or the LVESV (% denervation, r = 0.479, P < 0.001; H/M ratio, r =  -0.450, P < 0.001; and WR, r = 0.520, P < 0.001) in the statin group. In contrast, there was no relationship between these parameters in the non-statin group.Statin therapy not only improved CSNA, but also reduced LV volume, in other wards, prevented LV remodeling in CHF patients.

Effects of oral nicorandil therapy on sympathetic nerve activity and cardiac events in patients with chronic heart failure: subanalysis of our previous report using propensity score matching

PURPOSE

Nicorandil, an adenosine triphosphate-sensitive potassium channel opener, improves cardiac sympathetic nerve activity (CSNA) in patients with ischaemic heart disease. However, the long-term effects on both CSNA, as evaluated by (123)I-metaiodobenzylguanidine (MIBG) scintigraphy, and prognosis have not been determined in patients with chronic heart failure (CHF).

METHODS

This study was a subanalysis of our previous results that serial (123)I-MIBG scintigraphic studies are the most useful prognostic indicator in CHF patients. The study group comprised 208 patients with CHF (left ventricular ejection fraction <45 %) but no cardiac events for at least 5 months identified on the basis of a history of decompensated acute heart failure requiring hospitalization. These patients underwent (123)I-MIBG scintigraphy and echocardiography just before leaving the hospital and again 6 months later. We selected 170 patients and used propensity propensity score matching to compare patients who received oral nicorandil (85 patients) and those who did not (85 patients). The patients were followed up for a median of 5.03 years, with the primary and secondary study end-points defined as the occurrence of a fatal cardiac event and a major adverse cardiac event (MACE), respectively.

RESULTS

After treatment, the extent of changes in (123)I-MIBG scintigraphic and echocardiographic parameters in the nicorandil group were more favourable than in those not receiving nicorandil. Of the 170 patients, a fatal cardiac event occurred in 42, and a MACE in 68 during the study. Multivariate Cox regression analyses revealed that no nicorandil treatment was a significant predictor of both cardiac death and MACE in our patients with CHF. On Kaplan-Meier analysis, the rates of freedom from cardiac death or from MACE in the nicorandil group were significantly higher than in those not receiving nicorandil (all p<0.05).

CONCLUSION

Long-term nicorandil treatment improves CSNA and left ventricular parameters in patients with CHF. Furthermore, this agent is potentially effective for reducing the incidence of cardiac events in patients with CHF.

Relationship between late ventricular potentials and myocardial 123I-metaiodobenzylguanidine scintigraphy in patients with dilated cardiomyopathy with mild to moderate heart failure: results of a prospective study of sudden death events

PURPOSE

Late ventricular potentials (LPs) are considered to be useful for identifying patients with heart failure at risk of developing ventricular arrhythmias. (123)I-metaiodobenzylguanidine (MIBG) scintigraphy, which is used to evaluate cardiac sympathetic activity, has demonstrated cardiac sympathetic denervation in patients with malignant ventricular tachyarrhythmias. This study was undertaken to clarify the relationship between LPs and (123)I-MIBG scintigraphy findings in patients with dilated cardiomyopathy (DCM).

METHODS

A total of 56 patients with DCM were divided into an LP-positive group (n = 24) and an LP-negative group (n = 32). During the compensated period, the delayed heart/mediastinum count (H/M) ratio, delayed total defect score (TDS), and washout rate (WR) were determined from (123)I-MIBG images and plasma brain natriuretic peptide (BNP) concentrations were measured. Left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), and left ventricular ejection fraction (LVEF) were simultaneously determined by echocardiography.

RESULTS

LVEDV, LVESV, LVEF and plasma BNP concentrations were similar in the two groups. However, TDS was significantly higher (35 ± 8 vs. 28 ± 6, p < 0.005), the H/M ratio was significantly lower (1.57 ± 0.23 vs. 1.78 ± 0.20, p < 0.005), and the WR was significantly higher (60 ± 14% vs. 46 ± 12%, p < 0.001) in the LP-positive than in the LP-negative group. The average follow-up time was 4.5 years, and there were nine sudden deaths among the 56 patients (16.1%). In logistic regression analysis, the incidences of sudden death events were similar in those LP-negative with WR <50%, LP-negative with WR ≥ 50% and LP-positive with WR <50% (0%, 10.0% and 14.3%, respectively), but was significantly higher (41.2%) in those LP-positive with WR ≥ 50% (p < 0.01, p < 0.05, and p < 0.05, respectively).

CONCLUSION

The present study demonstrated that the values of cardiac (123)I-MIBG scintigraphic parameters were worse in LP-positive DCM patients than in LP-negative DCM patients. Furthermore, in LP-positive DCM patients with a high WR, the incidence of sudden death events was higher than that in other subgroups of DCM patients.

Cardiac iodine-123 metaiodobenzylguanidine (123I-MIBG) scintigraphy parameter predicts cardiac and cerebrovascular events in type 2 diabetic patients without structural heart disease

BACKGROUND

Cardiac iodine-123 metaiodobenzylguanidine ((123)I-MIBG) scintigraphy is an established method of assessment of cardiovascular sympathetic function. The aim of the present study was to investigate the long-term cardiovascular predictive value of cardiac (123)I-MIBG scintigraphy parameters in Japanese type 2 diabetic patients without structural heart disease.

METHODS AND RESULTS

Cardiac (123)I-MIBG scintigraphy in 108 patients with type 2 diabetes who did not have structural heart disease, was evaluated. The washout rate (WR) was considered enhanced if it was ≥40%. Accurate follow-up information for 4.6 years was obtained in 54 enhanced WR patients (27 male; mean age, 61 ± 11 years) and in 54 sex- and age-matched preserved WR patients (27 male; mean age, 61 ± 10 years). Major adverse cardiac and cerebrovascular events (MACCE) were investigated. During follow-up, 10 enhanced WR patients developed MACCE including cardiac death, coronary revascularization, stroke, and congestive heart failure, while MACCE occurred in only 3 male patients. The Kaplan-Meier curves indicated that enhanced WR patients had higher incidence of MACCE than those with preserved WR (P<0.05). Cox proportional hazards regression analysis showed that age and enhanced WR were independently associated with the incidence of MACCE (hazard ratio, 4.06; 95% confidence interval: 1.194-18.76, P = 0.0237).

CONCLUSIONS

Abnormal WR of cardiac (123)I-MIBG scintigraphy at baseline has long-term cardiovascular predictive value in Japanese patients with type 2 diabetes without structural heart disease.