Guilhermina Cantinho

Reduced myocardial 123-iodine metaiodobenzylguanidine uptake: a prognostic marker in familial amyloid polyneuropathy.

Background— Transthyretin familial amyloid polyneuropathy is a hereditary form of amyloidosis characterized by sensorimotor and autonomic neuropathy, cardiac conduction defects, and infiltrative cardiomyopathy. Previous studies have suggested that myocardial sympathetic denervation assessed by 123-iodine metaiodobenzylguanidine (MIBG) imaging occurs early in disease progression. However, its prognostic significance was never evaluated. We aimed to study the long-term prognostic value of myocardial sympathetic denervation detected by MIBG imaging in transthyretin familial amyloid polyneuropathy. Methods and Results— A total of 143 individuals with V30M transthyretin mutation underwent Holter, ambulatory blood pressure monitoring, echocardiography, and MIBG imaging. Time to all-cause death was compared with late heart-to-mediastinum MIBG uptake ratio (H/M; either in relation to the estimated lower limit of normal [1.60] or as a continuous variable) using Cox proportional hazards regression. Multivariable analyses were performed to test the prognostic accuracy of clinical, neurological, and cardiovascular parameters. During a median follow-up of 5.5 years, 32 (22%) patients died. Five-year mortality rate was 42% for late H/M <1.60 and 7% for late H/M ≥1.60 (hazard ratio, 7.19; P <0.001). Late H/M was identified as an independent prognostic predictor. Fifty-three patients were submitted to liver transplantation. In comparison with neurophysiological score–matched controls, transplanted patients had lower long-term mortality (hazard ratio, 0.32; P =0.012). Patients with late H/M<1.60 were at higher risk of unfavorable outcome but seemed to have benefited from liver transplantation. Conclusions— Cardiac sympathetic denervation as assessed by MIBG imaging is a useful prognostic marker in transthyretin familial amyloid polyneuropathy.Background— Transthyretin familial amyloid polyneuropathy is a hereditary form of amyloidosis characterized by sensorimotor and autonomic neuropathy, cardiac conduction defects, and infiltrative cardiomyopathy. Previous studies have suggested that myocardial sympathetic denervation assessed by 123-iodine metaiodobenzylguanidine (MIBG) imaging occurs early in disease progression. However, its prognostic significance was never evaluated. We aimed to study the long-term prognostic value of myocardial sympathetic denervation detected by MIBG imaging in transthyretin familial amyloid polyneuropathy. Methods and Results— A total of 143 individuals with V30M transthyretin mutation underwent Holter, ambulatory blood pressure monitoring, echocardiography, and MIBG imaging. Time to all-cause death was compared with late heart-to-mediastinum MIBG uptake ratio (H/M; either in relation to the estimated lower limit of normal [1.60] or as a continuous variable) using Cox proportional hazards regression. Multivariable analyses were performed to test the prognostic accuracy of clinical, neurological, and cardiovascular parameters. During a median follow-up of 5.5 years, 32 (22%) patients died. Five-year mortality rate was 42% for late H/M <1.60 and 7% for late H/M ≥1.60 (hazard ratio, 7.19; P<0.001). Late H/M was identified as an independent prognostic predictor. Fifty-three patients were submitted to liver transplantation. In comparison with neurophysiological score–matched controls, transplanted patients had lower long-term mortality (hazard ratio, 0.32; P=0.012). Patients with late H/M<1.60 were at higher risk of unfavorable outcome but seemed to have benefited from liver transplantation. Conclusions— Cardiac sympathetic denervation as assessed by MIBG imaging is a useful prognostic marker in transthyretin familial amyloid polyneuropathy.

Reduced Myocardial 123-Iodine Meta-iodobenzylguanidine Uptake: A Prognostic Marker in Familial Amyloid Polyneuropathy

Background— Transthyretin familial amyloid polyneuropathy is a hereditary form of amyloidosis characterized by sensorimotor and autonomic neuropathy, cardiac conduction defects, and infiltrative cardiomyopathy. Previous studies have suggested that myocardial sympathetic denervation assessed by 123-iodine metaiodobenzylguanidine (MIBG) imaging occurs early in disease progression. However, its prognostic significance was never evaluated. We aimed to study the long-term prognostic value of myocardial sympathetic denervation detected by MIBG imaging in transthyretin familial amyloid polyneuropathy. Methods and Results— A total of 143 individuals with V30M transthyretin mutation underwent Holter, ambulatory blood pressure monitoring, echocardiography, and MIBG imaging. Time to all-cause death was compared with late heart-to-mediastinum MIBG uptake ratio (H/M; either in relation to the estimated lower limit of normal [1.60] or as a continuous variable) using Cox proportional hazards regression. Multivariable analyses were performed to test the prognostic accuracy of clinical, neurological, and cardiovascular parameters. During a median follow-up of 5.5 years, 32 (22%) patients died. Five-year mortality rate was 42% for late H/M <1.60 and 7% for late H/M ≥1.60 (hazard ratio, 7.19; P <0.001). Late H/M was identified as an independent prognostic predictor. Fifty-three patients were submitted to liver transplantation. In comparison with neurophysiological score–matched controls, transplanted patients had lower long-term mortality (hazard ratio, 0.32; P =0.012). Patients with late H/M<1.60 were at higher risk of unfavorable outcome but seemed to have benefited from liver transplantation. Conclusions— Cardiac sympathetic denervation as assessed by MIBG imaging is a useful prognostic marker in transthyretin familial amyloid polyneuropathy.Background— Transthyretin familial amyloid polyneuropathy is a hereditary form of amyloidosis characterized by sensorimotor and autonomic neuropathy, cardiac conduction defects, and infiltrative cardiomyopathy. Previous studies have suggested that myocardial sympathetic denervation assessed by 123-iodine metaiodobenzylguanidine (MIBG) imaging occurs early in disease progression. However, its prognostic significance was never evaluated. We aimed to study the long-term prognostic value of myocardial sympathetic denervation detected by MIBG imaging in transthyretin familial amyloid polyneuropathy. Methods and Results— A total of 143 individuals with V30M transthyretin mutation underwent Holter, ambulatory blood pressure monitoring, echocardiography, and MIBG imaging. Time to all-cause death was compared with late heart-to-mediastinum MIBG uptake ratio (H/M; either in relation to the estimated lower limit of normal [1.60] or as a continuous variable) using Cox proportional hazards regression. Multivariable analyses were performed to test the prognostic accuracy of clinical, neurological, and cardiovascular parameters. During a median follow-up of 5.5 years, 32 (22%) patients died. Five-year mortality rate was 42% for late H/M <1.60 and 7% for late H/M ≥1.60 (hazard ratio, 7.19; P<0.001). Late H/M was identified as an independent prognostic predictor. Fifty-three patients were submitted to liver transplantation. In comparison with neurophysiological score–matched controls, transplanted patients had lower long-term mortality (hazard ratio, 0.32; P=0.012). Patients with late H/M<1.60 were at higher risk of unfavorable outcome but seemed to have benefited from liver transplantation. Conclusions— Cardiac sympathetic denervation as assessed by MIBG imaging is a useful prognostic marker in transthyretin familial amyloid polyneuropathy.

Progressão da desnervação simpática cardíaca avaliada por cintigrafia com MIBG‐I123 na polineuropatia amiloidótica familiar e o impacto da transplantação hepática

INTRODUCTION Familial amyloid polyneuropathy (FAP) is a rare disease caused by systemic deposition of amyloidogenic variants of the transthyretin (TTR) protein. The TTR-V30M mutation is caused by the substitution of valine by methionine at position 30 and mainly affects the peripheral and autonomic nervous systems. Cardiovascular manifestations are common and are due to autonomic denervation and to amyloid deposition in the heart. Cardiac sympathetic denervation detected by iodine-123 labeled metaiodobenzylguanidine (MIBG) is an important prognostic marker in TTR-V30M FAP. Liver transplantation, widely used to halt neurological involvement, appears to have a varying effect on the progression of amyloid cardiomyopathy. Its effect on the progression of cardiac denervation remains unknown. METHODS In this observational study, patients with the TTR-V30M mutation underwent annual cardiac assessment and serial MIBG imaging with quantification of the late heart-to-mediastinum (H/M) ratio. RESULTS We studied 232 patients (median age 40 years, 54.7% female, 37.9% asymptomatic at the time of inclusion) who were followed for a median of 4.5 years and underwent a total of 558 MIBG scans. During follow-up, 47 patients (20.3%) died. MIBG scintigraphy at inclusion was a strong predictor of prognosis, with the risk of death increasing by 27.8% for each one-tenth reduction in the late H/M ratio. The late H/M ratio decreased with age (0.082/year, p<0.001), but progression of cardiac denervation was so slow that annual repetition of MIBG imaging did not increase its prognostic accuracy. During follow-up, 70 symptomatic patients underwent liver transplantation. The late H/M ratio decreased by 0.19/year until transplantation but no statistically significant differences were detected after the procedure. CONCLUSIONS Cardiac denervation is common during the progression of TTR-V30M FAP and quantification of the late H/M ratio on MIBG scintigraphy is valuable for prognostic stratification of these patients. Liver transplantation stabilizes cardiac denervation, without recovery or further deterioration in cardiac MIBG uptake after the procedure.

HOW USEFUL IS 99MTC-DPD SCINTIGRAPHY IN DIAGNOSIS OF CARDIAC AMYLOIDOSIS IN TRANSTHYRETIN V30M FAMILIAL AMYLOID POLYNEUROPATHY?

Background: Previous studies suggested that 99mTc-3,3-diphosphono-1,2-propanodicarboxylic acid (DPD) scintigraphy may be useful for early diagnosis of hereditary transthyretin (TTR) related cardiac amyloidosis. However its diagnostic value in V30M TTR familial amyloid polyneuropathy (FAP) remains

Reduced Myocardial 123-Iodine Metaiodobenzylguanidine UptakeClinical Perspective: A Prognostic Marker in Familial Amyloid Polyneuropathy

Background— Transthyretin familial amyloid polyneuropathy is a hereditary form of amyloidosis characterized by sensorimotor and autonomic neuropathy, cardiac conduction defects, and infiltrative cardiomyopathy. Previous studies have suggested that myocardial sympathetic denervation assessed by 123-iodine metaiodobenzylguanidine (MIBG) imaging occurs early in disease progression. However, its prognostic significance was never evaluated. We aimed to study the long-term prognostic value of myocardial sympathetic denervation detected by MIBG imaging in transthyretin familial amyloid polyneuropathy. Methods and Results— A total of 143 individuals with V30M transthyretin mutation underwent Holter, ambulatory blood pressure monitoring, echocardiography, and MIBG imaging. Time to all-cause death was compared with late heart-to-mediastinum MIBG uptake ratio (H/M; either in relation to the estimated lower limit of normal [1.60] or as a continuous variable) using Cox proportional hazards regression. Multivariable analyses were performed to test the prognostic accuracy of clinical, neurological, and cardiovascular parameters. During a median follow-up of 5.5 years, 32 (22%) patients died. Five-year mortality rate was 42% for late H/M <1.60 and 7% for late H/M ≥1.60 (hazard ratio, 7.19; P <0.001). Late H/M was identified as an independent prognostic predictor. Fifty-three patients were submitted to liver transplantation. In comparison with neurophysiological score–matched controls, transplanted patients had lower long-term mortality (hazard ratio, 0.32; P =0.012). Patients with late H/M<1.60 were at higher risk of unfavorable outcome but seemed to have benefited from liver transplantation. Conclusions— Cardiac sympathetic denervation as assessed by MIBG imaging is a useful prognostic marker in transthyretin familial amyloid polyneuropathy.Background— Transthyretin familial amyloid polyneuropathy is a hereditary form of amyloidosis characterized by sensorimotor and autonomic neuropathy, cardiac conduction defects, and infiltrative cardiomyopathy. Previous studies have suggested that myocardial sympathetic denervation assessed by 123-iodine metaiodobenzylguanidine (MIBG) imaging occurs early in disease progression. However, its prognostic significance was never evaluated. We aimed to study the long-term prognostic value of myocardial sympathetic denervation detected by MIBG imaging in transthyretin familial amyloid polyneuropathy. Methods and Results— A total of 143 individuals with V30M transthyretin mutation underwent Holter, ambulatory blood pressure monitoring, echocardiography, and MIBG imaging. Time to all-cause death was compared with late heart-to-mediastinum MIBG uptake ratio (H/M; either in relation to the estimated lower limit of normal [1.60] or as a continuous variable) using Cox proportional hazards regression. Multivariable analyses were performed to test the prognostic accuracy of clinical, neurological, and cardiovascular parameters. During a median follow-up of 5.5 years, 32 (22%) patients died. Five-year mortality rate was 42% for late H/M <1.60 and 7% for late H/M ≥1.60 (hazard ratio, 7.19; P<0.001). Late H/M was identified as an independent prognostic predictor. Fifty-three patients were submitted to liver transplantation. In comparison with neurophysiological score–matched controls, transplanted patients had lower long-term mortality (hazard ratio, 0.32; P=0.012). Patients with late H/M<1.60 were at higher risk of unfavorable outcome but seemed to have benefited from liver transplantation. Conclusions— Cardiac sympathetic denervation as assessed by MIBG imaging is a useful prognostic marker in transthyretin familial amyloid polyneuropathy.

Reduced Myocardial 123-Iodine Metaiodobenzylguanidine UptakeClinical Perspective

Background— Transthyretin familial amyloid polyneuropathy is a hereditary form of amyloidosis characterized by sensorimotor and autonomic neuropathy, cardiac conduction defects, and infiltrative cardiomyopathy. Previous studies have suggested that myocardial sympathetic denervation assessed by 123-iodine metaiodobenzylguanidine (MIBG) imaging occurs early in disease progression. However, its prognostic significance was never evaluated. We aimed to study the long-term prognostic value of myocardial sympathetic denervation detected by MIBG imaging in transthyretin familial amyloid polyneuropathy. Methods and Results— A total of 143 individuals with V30M transthyretin mutation underwent Holter, ambulatory blood pressure monitoring, echocardiography, and MIBG imaging. Time to all-cause death was compared with late heart-to-mediastinum MIBG uptake ratio (H/M; either in relation to the estimated lower limit of normal [1.60] or as a continuous variable) using Cox proportional hazards regression. Multivariable analyses were performed to test the prognostic accuracy of clinical, neurological, and cardiovascular parameters. During a median follow-up of 5.5 years, 32 (22%) patients died. Five-year mortality rate was 42% for late H/M <1.60 and 7% for late H/M ≥1.60 (hazard ratio, 7.19; P <0.001). Late H/M was identified as an independent prognostic predictor. Fifty-three patients were submitted to liver transplantation. In comparison with neurophysiological score–matched controls, transplanted patients had lower long-term mortality (hazard ratio, 0.32; P =0.012). Patients with late H/M<1.60 were at higher risk of unfavorable outcome but seemed to have benefited from liver transplantation. Conclusions— Cardiac sympathetic denervation as assessed by MIBG imaging is a useful prognostic marker in transthyretin familial amyloid polyneuropathy.Background— Transthyretin familial amyloid polyneuropathy is a hereditary form of amyloidosis characterized by sensorimotor and autonomic neuropathy, cardiac conduction defects, and infiltrative cardiomyopathy. Previous studies have suggested that myocardial sympathetic denervation assessed by 123-iodine metaiodobenzylguanidine (MIBG) imaging occurs early in disease progression. However, its prognostic significance was never evaluated. We aimed to study the long-term prognostic value of myocardial sympathetic denervation detected by MIBG imaging in transthyretin familial amyloid polyneuropathy. Methods and Results— A total of 143 individuals with V30M transthyretin mutation underwent Holter, ambulatory blood pressure monitoring, echocardiography, and MIBG imaging. Time to all-cause death was compared with late heart-to-mediastinum MIBG uptake ratio (H/M; either in relation to the estimated lower limit of normal [1.60] or as a continuous variable) using Cox proportional hazards regression. Multivariable analyses were performed to test the prognostic accuracy of clinical, neurological, and cardiovascular parameters. During a median follow-up of 5.5 years, 32 (22%) patients died. Five-year mortality rate was 42% for late H/M <1.60 and 7% for late H/M ≥1.60 (hazard ratio, 7.19; P<0.001). Late H/M was identified as an independent prognostic predictor. Fifty-three patients were submitted to liver transplantation. In comparison with neurophysiological score–matched controls, transplanted patients had lower long-term mortality (hazard ratio, 0.32; P=0.012). Patients with late H/M<1.60 were at higher risk of unfavorable outcome but seemed to have benefited from liver transplantation. Conclusions— Cardiac sympathetic denervation as assessed by MIBG imaging is a useful prognostic marker in transthyretin familial amyloid polyneuropathy.