The cardiomyopathy of cystic fibrosis: a modern form of Keshan disease.

Introduction: We conducted a study to determine the prevalence of structural heart disease in patients with CF, the characteristics of a cardiomyopathy not previously described in this population, and its possible relationship with nutritional deficiencies in CF. Methods: We studied 3 CMP CF patients referred for heart-lung transplantation and a prospective series of 120 adult CF patients. All patients underwent a clinical examination, blood tests including levels of vitamins and trace elements, and echocardiography with evaluation of myocardial strain. Cardiac magnetic resonance imaging (CMR) was performed in patients with CMP and in a control group. Histopathological study was performed on hearts obtained in transplant or necropsy. Results: We found a prevalence of 10% (CI 4.6%-15.4%) of left ventricular (LV) dysfunction in the prospective cohort. Myocardial strain parameters were already altered in CF patients with otherwise normal hearts. Histopathological examination of 4 hearts from CF CMP patients showed a unique histological pattern of multifocal myocardial fibrosis similar to Keshan disease. Four of the five CF CMP patients undergoing CMR showed late gadolinium uptake, with a characteristic patchy pattern in 3 cases (p < 0.001 vs. CF controls). Selenium deficiency (Se < 60 µg/L) was associated with more severe LV dysfunction, higher prevalence of CF CMP, higher NTproBNP levels, and more severe pulmonary and digestive involvement. Conclusion: 10% of adults with CF showed significant cardiac involvement, with histological and imaging features resembling Keshan disease. Selenium deficiency was associated with the presence and severity of LV dysfunction in these patients.

Role of Right Ventricular Strain Measured by Two-Dimensional Echocardiography in the Diagnosis of Cardiac Amyloidosis.

BACKGROUND: Cardiac amyloidosis (CA) causes restrictive cardiomyopathy usually associated with a poor prognosis. Two subtypes predominate: systemic light-chain CA (ALCA) and transthyretin-derived CA (either wild type transthyretin amyloidosis [TTRwt] or mutant transthyretin amyloidosis [TTRm]). Left ventricular (LV) apical sparing has been extensively studied using speckle-tracking echocardiography for diagnosis, but the right ventricular (RV) deformation pattern has not been described. The aims of this study were to characterize RV involvement in patients with CA and to identify parameters that may help in the differential diagnosis between ALCA and transthyretin-derived CA subtypes. METHODS: Seventy-eight patients with CA (47 with ALCA, 20 with TTRwt, and 11 with TTRm) and 24 healthy control subjects were included. Global longitudinal strain (GLS) was analyzed in 16 LV and six RV segments. LV and RV apical ratios (ARs) were obtained. GLS was expressed as an absolute value. RESULTS: LV GLS and free-wall RV longitudinal strain were impaired in all patients (LV GLS: 11.9 ± 2.9% in ALCA, 12.5 ± 3.8% in TTRwt, 14.9 ± 2.7% in TTRm, and 21.9 ± 2.6% in control subjects [P < .01]; free-wall RV longitudinal strain: 13.1 ± 6.8%, 14.9 ± 4.5%, 17.2 ± 3.4%, and 22.1 ± 3.1%, respectively [P < .01]). LV and RV ARs were higher in ALCA compared with both TTRwt, TTRm, and control subjects (LV AR: 1.1 ± 0.2, 0.8 ± 0.2, 0.9 ± 0.1, and 0.7 ± 0.1, respectively [P < .001]; RV AR: 1.1 ± 0.2, 0.6 ± 0.2, 0.6 ± 0.1, and 0.6 ± 0.1, respectively [P < .001]). Cutoff values of LV AR > 0.96 and RV AR > 0.8 showed high accuracy to differentiate between ALCA and transthyretin-derived CA. CONCLUSIONS: RV dysfunction is common in patients with CA. Analysis of RV strain showed an apical sparing pattern, as previously described in the left ventricle, with a higher AR as a specific finding in patients with ALCA. RV AR may be a parameter that can differentiate the subtypes of amyloidosis on the basis of speckle-tracking echocardiographic analysis.

Two-Dimensional Speckle Tracking Echocardiography in Heart Transplant Patients: Two-Year Follow-Up of Right and Left Ventricular Function.

BACKGROUND: Evolution of left and right ventricular (LV and RV) function after heart transplantation (HT) has not been well described. Our objective was to evaluate the evolution of echocardiographic parameters of both ventricles along the first 2 years after HT. METHODS: We followed 31 HT recipients with serial echocardiograms for up to 2 years. Echocardiograms with AR ≥2R were excluded. We analyzed LV global longitudinal strain (LV GLS) by speckle tracking in 12 segments in four- and two-chamber views and RV global longitudinal strain (RV GLS) in four-chamber view. Control group included 25 healthy volunteers. RESULTS: Even though LVEF was preserved, LV GLS was reduced early post-HT (-17.7 ± 3.0 in HT vs. -20.7 ± 2.8 in controls, P = 0.02), improving progressively until its complete normalization 2 years after HT (-20.0 ± 3.7 vs. -20.7 ± 2.8, P = 0.60). TAPSE was impaired in the early post-HT period and increased progressively (11.9 ± 2.9 mm at baseline vs. 19.0 ± 3.6 mm at 2 years, P < 0.001). RV GLS rose during follow-up as well (-17.4 ± 3.5 at baseline vs. -22.6 ± 3.3 at 2 years, P = 0.001), reaching normal values 1 year after HT. CONCLUSION: In this series of HT recipients with uneventful postoperative course, LV and RV GLS values were significantly reduced early after HT and improved progressively until their complete normalization two and 1 year after HT, respectively. This is the first study to show a full recovery of LV and RV deformation parameters and offers "normal" strain values that, if confirmed in larger studies, could be useful for monitoring the evolution of HT recipients.

[Maze technique for the treatment of auricular fibrillation: initial experience]. / Técnica de MAZE para el tratamiento de la fibrilacion auricular: experiencia inicial.

INTRODUCTION AND OBJECTIVES: The MAZE procedure was developed as a surgical approach to the management of patients with atrial fibrillation refractory to medical treatment. This study seeks to identify the risk and benefits of adding the MAZE procedure in patients with atrial fibrillation undergoing surgery for underlying organic cardiac disorders. MATERIAL AND METHODS: Since november 1993, we have performed 10 interventions with the MAZE procedure, for the treatment of refractory atrial fibrillation. The indication to perform the technique was systemic embolism in 5 patients, contraindication for the anticoagulant treatment in two cases and no response to antiarrhythmic treatment in 5 cases. Two patients had more than one indication. In all the cases another surgical procedure was performed, 5 replacements of mitral valve, a mitral repair, one tricuspid repair and tree repairs of an atrial septal defect. RESULTS: Soon after surgery 9 patients were in sinus rhythm, and one in atrial fibrillation. Four patients needed atrial pacing during the first days. One patient required a pacemaker due to symptomatic sinus bradycardia. During the first 3 months, 4 patients had episodes of paroxysmal atrial fibrillation and flutter. One patient died suddenly one month after surgery. Seven patients have completed two years of follow-up, and are in stable sinus rhythm, in functional class I and free of antiarrhythmic drugs. All of them have echocardiographic evidence of mechanical activity in both atria. Left atrium had been reduced from 5.3 +/- 0.7 cm to 4.5 +/- 0.7 cm (p < 0.05). No patient has presented new embolic events. CONCLUSIONS: The MAZE procedure is a good choice in selected patients with atrial fibrillation refractory to medical treatment, or a precedent of systemic embolism. However, several problems can complicate the patient's course.

[Surgical treatment of atrial fibrillation]. / Tratamiento quirúrgico de la fibrilación auricular.

Atrial fibrillation is the most frequently found sustained arrhythmia. It increases the risk of thromboembolism and adversely affects cardiac performance because of loss of atrial kick. New surgical treatments of atrial fibrillation have been developed to ablate the origin of abnormal impulses on the atrium. The left atrial isolation and the corridor operation restores the regular rhythm, but do not reduce the risk of thromboembolism because the left atrium may continue to fibrillate. The maze operation has proven to be effective in both converting to sinus rhythm and regaining atrial contractility. However, this method is meticulous and time-consuming and takes more cardiac ischemic time, especially when other cardiac procedures are performed simultaneously.