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Background: TRACS sought to describe the clinical outcomes and disease progression of transthyretin (TTR) cardiac amyloidosis (ATTR) in an observational study. Clinical course is largely determined by disease type with ATTR categorized as wild-type (ATTRwt) or genetic-variant protein (ATTRm). Prospective data are lacking in the most common TTR mutation, V122I, present in approximately 3.5% of African Americans., Methods: Patients with ATTRwt (n = 18) and V122I ATTRm (n = 11) were longitudinally assessed every 6 months for up to 2 years by functional class assessments, biochemical markers, and echocardiography., Results: At baseline, no differences in clinical characteristics, biomarkers, or echocardiographic parameters were noted between patients with ATTRwt and patients with ATTRm. After 15.5 ± 8 months, there were 11 deaths and 1 cardiac transplant, with higher mortality (73% vs 22%, P = .03) and cardiovascular hospitalization (64% vs 28%, P = .02) among patients with ATTRm. The median survival from diagnosis was 25.6 months for ATTRm vs 43.0 months for ATTRwt (P = .04). Univariate predictors of mortality included disease duration, heart rate ≥ 70 beats/min, baseline stroke volume, left ventricular ejection fraction <50%, and ATTRm status. For each 6-month increment, the mean 6-minute walk distance declined by 25.8 m, N-terminal pro b-type natriuretic peptide increased by 1,816 pg/mL, and left ventricular ejection fraction fell by 3.2%, for the entire cohort., Conclusions: In this prospective study, disease progression, morbidity, and mortality were observed in ATTR cardiomyopathy, particularly due to V122I, over a short duration. Given the prevalence of this mutation, further study of V122I in at-risk African American patients is warranted., (Copyright © 2012 Mosby, Inc. All rights reserved.)

Background: Transthyretin (TTR) mutations known to cause cardiac amyloidosis include V122I, found almost exclusively in African Americans at a prevalence of 3-3.9%. This retrospective study describes TTR V122I-associated cardiac amyloid disease (ATTR) in a major amyloid referral clinic population., Methods: Self-identified African Americans with amyloidosis (n = 156) were screened for TTR V122I by serum isoelectric focusing; mutant TTR was confirmed by DNA sequencing or mass spectrometry. Cardiac findings in ATTR V122I and immunoglobulin light chain (AL) amyloidoses were compared., Results: TTR V122I was identified in 36/156 (23.1%) of evaluated patients and included 5 homozygotes; the allele frequency was 0.013. One compound heterozygote (F44L/V122I) and 4 patients who had AL and the mutant TTR allele were characterized. In patients negative for V122I, AL was the most frequent diagnosis (86/120). Cardiomyopathy was present in 100% of patients with ATTR and 84% of patients with AL (P = .01). In patients with dominant cardiac involvement, better survival occurred in ATTR (n = 30) compared to AL (n = 31), (27 vs 5 months, P < .01) although the mean age in ATTR was higher (70.3 vs 56.2 years, P < .01). Congestive heart failure symptoms and electrocardiographic findings were similar in ATTR and AL, but significant differences in echocardiographic measurements were observed., Conclusions: ATTR V122I and AL are equally prevalent as the cause of cardiomyopathy in African Americans referred for a diagnosis of amyloidosis. Available therapy for AL underscores the need for early and accurate determination of amyloid type.

We report the identification of a new transthyretin (TTR) gene mutation and variant protein, Glu61Gly, in a 55-year-old man with progressive cardiomyopathy, mild peripheral neuropathy and bilateral carpal tunnel syndrome. A diagnosis of TTR-associated familial amyloidosis (ATTR) was considered after an endomyocardial biopsy revealed amyloid deposits in the heart of a patient who had no family history of amyloidosis and no evidence of a plasma cell dyscrasia. Serum screening for a TTR variant by isoelectric focusing (IEF) was positive and prompted further studies to identify the genetic abnormality and to characterize the amyloidogenic protein. Direct DNA sequence analysis of all four coding regions in the TTR gene demonstrated heterozygosity in exon 3. Near equal amounts of guanine (G) and adenine (A) were observed at the second base position of codon 61. The wild-type (GAG) and mutated (GGG) sequences found in codon 61 correspond to glutamic acid (Glu) and glycine (Gly) residues, amino acids which differ in mass by -72 Da. Mass spectrometric analyses of TTR immunoprecipitated from serum showed the presence of both wild-type and variant proteins. The observed mass results for the wild-type and variant proteins were consistent with the predicted values calculated from the genetic analysis data.

Cardiac amyloidosis is a well-known but clinically rare cause of heart failure that has historically been associated with a poor prognosis. Cardiac amyloidosis involves fibril formation from one of several underlying conditions, and the course of illness and prognosis varies among these conditions. Evolving treatment strategies for patients with primary systemic amyloidosis have given this subset of cardiac amyloidosis patients a cause for hope. The identification and appropriate referral of patients in whom this condition is suspected will help to improve the likelihood of successful therapy and long-term survival.

This study sought to determine plasma levels of B-natriuretic peptide (BNP) in patients with light-chain-associated amyloidosis and correlate them with the presence or absence of heart failure (HF) and the presence or absence of echocardiographic abnormalities. Patients with normal echocardiographic results had significantly lower BNP levels than those with echocardiographic features of cardiac amyloidosis, whereas BNP levels in the group with HF did not differ from those in patients with asymptomatic cardiac amyloidosis. This observation supports previous observations, suggesting that the elevation of BNP in cardiac amyloidosis may be due not only to elevated ventricular filling pressure but also to direct myocyte damage due to extracellular deposits of amyloid.

Background: Small deposits of amyloid are often found in the hearts of elderly patients. However, extensive deposition of transthyretin-derived amyloid fibrils in the heart (senile systemic amyloidosis [SSA]) can cause heart failure. The clinical features of SSA that involve the heart are ill defined, and the condition may be overlooked as a cause of heart failure. We sought to better define the clinical, echocardiographic, and electrocardiographic features of cardiac involvement in SSA and to compare them with the findings in patients with light chain-associated (AL) amyloidosis that affects the heart., Methods: Eighteen consecutive patients with SSA and heart failure evaluated at a tertiary referral center for the diagnosis and treatment of amyloidosis were compared with 18 randomly selected patients with AL amyloidosis that involved the heart. All patients underwent a complete clinical and biochemical evaluation. Echocardiograms and electrocardiograms were interpreted by blinded investigators., Results: Patients with SSA were older than those with AL amyloidosis and were all male. Proteinuria (protein output of >1 g per 24 hours) was common in AL amyloidosis but was not present in SSA. Left ventricular wall thickness was greater in patients with SSA than those with AL amyloidosis, but despite thicker walls and older age, the severity of heart failure was less in the SSA group and the median survival was much longer (75 vs 11 months; P = .003)., Conclusions: Senile systemic amyloidosis is a disorder of elderly men and is characterized by amyloidosis clinically limited to the heart. In contrast to the rapid progression of heart failure in AL amyloidosis, SSA results in slowly progressive heart failure. The difference in survival, despite evidence of more myocardial disease in the senile group, suggests that heart failure in AL amyloidosis may have a toxic component, possibly related to the circulating monoclonal light chain.

The identification of a rare transthyretin (TTR) gene mutation (Asp18Glu) in a middle-aged male with biopsy proven amyloid disease featuring cardiomyopathy is described. The more commonly occurring light chain amyloidosis (AL) was initially considered, but negative hematologic testing prompted screening for a pathologic TTR mutation. A differential diagnosis of familial transthyretin type amyloidosis (ATTR) was established using a combination of molecular genetic and biochemical techniques. Single-strand conformation polymorphism (SSCP) screening of exons 2, 3 and 4 of the TTR gene indicated the presence of atypical DNA. SSCP testing was performed using a new non-radioactive, silver stained minigel technique. The genetic abnormality was identified by direct DNA sequence analysis as a T to A transversion at the third base position in codon 18. This result was confirmed by restriction fragment length polymorphism (RFLP) testing. The presence of the variant protein, TTR Asp18Glu, in serum from the proband was confirmed by mass spectrometric analysis.

Background: AL amyloidosis is a fatal disease resulting from tissue deposition of amyloid fibrils derived from monoclonal immunoglobulin light chains. Treatment with oral chemotherapy is minimally effective.Objective: To test survival and organ response in a large sample of patients treated with high-dose intravenous melphalan (100 to 200 mg/m2) and autologous blood stem-cell transplantation.Design: 8-year longitudinal analysis of clinical effectiveness.Setting: University-affiliated specialty referral clinic.Patients: 701 consecutive new patients with AL amyloidosis.Intervention: High-dose chemotherapy and autologous stem-cell transplantation for patients who met eligibility requirements based on organ involvement and clinical status.Measurements: Survival analysis of all patients evaluated and a detailed analysis of treatment outcome in the subgroup that received high-dose melphalan and stem-cell transplantation.Results: Among 701 patients with AL amyloidosis, 394 (56%) were eligible for high-dose melphalan and stem-cell transplantation; 82 did not proceed with treatment because of patient choice or disease progression. Median survival of the 312 patients who initiated treatment was 4.6 years. A complete hematologic response, defined as no evidence of an underlying plasma cell dyscrasia 1 year after treatment, was achieved in 40% of patients and was associated with prolonged survival. Statistically significant improvements occurred in end-organ disease and were greater in patients with a complete hematologic response. Mortality rate within 100 days of treatment with high-dose melphalan and stem-cell transplantation was 13%; patients with cardiomyopathy had the highest mortality rates.Conclusions: Treatment of selected patients with AL amyloidosis by using high-dose melphalan and stem-cell transplantation resulted in hematologic remission, improved 5-year survival, and reversal of amyloid-related disease in a substantial proportion. [ABSTRACT FROM AUTHOR]

Familial amyloidotic polyneuropathy (FAP) is a protein folding disorder that induces neuropathy and cardiomyopathy, leading to death within 7-15 years after onset of clinical disease. In vitro, small ligands binding the thyroid hormone docking site stabilize tetrameric transthyretin, inhibiting amyloid fibril formation. We undertook a randomized, placebo-controlled clinical trial to determine whether diflunisal, a well-known non-steroidal anti-inflammatory drug (NSAID) alters neurologic disease progression in FAP. We enrolled 130 subjects with wide age and FAP mutation representation. To date, few recognized complications of NSAIDs have occurred in the study cohort. Data collection will be completed by November 2012. [ABSTRACT FROM AUTHOR]