Accelerating restrictive cardiomyopathy after liver transplantation in a patient with familial amyloidotic polyneuropathy: a case report.

INTRODUCTION: Hereditary amyloidodis is a rare disease process with a propensity to cause polyneuropathies, autonomic dysfunction, and restrictive cardiomyopathy. It is transmitted in an autosomal dominant manner, with disease onset usually in the 20s-40s. The most common hereditary amyloidogenic protein, transthyretin, is synthesized in the liver and lies on Chromosome 18. Over 80 amyloidogenic transthyretin mutations have been described, the majority of which are neuropathic and hence the common name, Familial Amyloidotic Polyneuropathy. Until 1990, the disease was intractable with a 5-15 year survival after diagnosis. The prognosis changed after the implementation of orthotropic liver transplantation as a treatment strategy which halts the synthesis of amyloidogenic transthyretin. This has now has been performed over 1300 times in 67 centers. CASE PRESENTATION: We describe the case of a man of Irish ancestry with Familial Amyloidotic Polyneuropathy and no clinical history of cardiac involvement. Shortly after orthotropic liver transplantation, he developed congestive heart failure. He was subsequently diagnosed with an accelerating post-transplant restrictive cardiomyopathy due to amyloid infiltration. CONCLUSION: A liver transplant induced cardiomyopathy in Familial Amyloidotic Polyneuropathy can be observed in patients without any history of cardiac symptoms. All patients with Familial Amyloidotic Polyneuropathy should be followed after transplantation to assess for a deterioration in cardiac function.

Left ventricular function during and after right ventricular pacing.

OBJECTIVES: The aim of this research was to evaluate right ventricular pacing effects on left ventricular function. BACKGROUND: Right ventricular pacing alters the ventricular activation sequence and reduces left ventricular ejection fraction (EF). It is unclear whether the observed reduction in EF can be completely attributed to the alteration in activation sequence. METHODS: Twelve subjects (eight women), mean age 68 +/- 12 years, with transvenous dual-chamber pacemakers, normal left ventricular function, and intact atrioventricular (AV) conduction were studied with serial-gated blood pool studies. Left ventricular EF was measured at a fixed rate after at least 1 week of atrial pacing only (baseline), during short-term (2 h) and mid-term (1 week) AV sequential pacing with a short AV delay, and after short- and mid-term AV pacing. RESULTS: Baseline EF was 66.5 +/- 4.5%. Short-term AV pacing resulted in a decrease in EF to 60.3 +/- 5.2% (p < 0.0002). After one week of AV pacing, there was a further decline in EF to 52.9 +/- 8.3% (p < 0.0001). After cessation of mid-term pacing, EF was 57.3 +/- 5.9% (p < 0.0001 vs. baseline). A total of 2, 5, 8, and 24 h later, EF remained depressed (59% to 60%, p < 0.007). At 32 h, EF was 62.9 +/- 7.6% (p < 0.11 compared with baseline). CONCLUSIONS: The abnormal activation sequence resulting from right ventricular pacing accounts for only part of the reduction in EF as mid-term pacing is associated with a lower EF than short-term pacing, and EF remains depressed after cessation of AV pacing. Changes in ventricular function induced by right ventricular pacing may account for some of its associated adverse effects.

Usefulness of plasma vitamin B(6), B(12), folate, homocysteine, and creatinine in predicting outcomes in heart transplant recipients.

Atherothrombotic complications are frequently seen in patients undergoing heart transplantation. These patients have high plasma total homocysteine concentrations associated with lower folate and vitamin B(6) levels. The relation between these metabolic abnormalities and the development of vascular complications, however, remains unclear. Fasting plasma total homocysteine, folate, vitamin B(12), vitamin B(6), and creatinine were measured in 160 cardiac transplant recipients who were followed for a mean duration of 28 +/- 9 months after blood draw (mean 59 +/- 28 months after transplant). Cardiovascular events and causes of mortality were determined and Cox proportional-hazards regression analysis was used to identify the independent predictors for cardiovascular events and mortality. Twenty-five patients developed cardiovascular events and 17 died (11 cardiovascular deaths). Mean +/- SD total homocysteine value was 18.4 +/- 8.5 (range 4.3 to 63.5 micromol/L). Hyperhomocysteinemia (> or =15 micromol/L) was seen in 99 patients (62%). Levels were no different in patients with or without cardiovascular complications/death (16.8 +/- 6.2 vs 18.9 +/- 9 micromol/L, p = 0.4). However, vitamin B(6) deficiency was seen in 21% of recipients with and in 9% without cardiovascular complications/death (p = 0.05). The relative risk for cardiovascular events, including cardiovascular death, increased 2.7 times (confidence interval 1.2 to 5.9) for B(6) levels < or =20 nmol/L compared with those with normal B(6) levels (p = 0.02). Thus, hyperhomocysteinemia is common in transplant recipients but may have no causal role in the atherothrombotic vascular complications of transplantation. Deficiency of vitamin B(6), however, may predict adverse outcomes, suggesting a possible role for supplementation with this vitamin.