Amiodarone-Induced Thyrotoxicosis Recurrence After Amiodarone Reintroduction.

Reintroduction of amiodarone in patients with a history of amiodarone-induced thyrotoxicosis (AIT) is rarely used. To date, the risk of AIT recurrence after amiodarone reintroduction is unpredicted. The aim of the study was to evaluate the risk of AIT recurrence. Retrospectively, from 2000 to 2011, all euthyroid patients with a history of AIT with amiodarone reintroduction were included. Type and severity of the first AIT, amiodarone chronology, and thyroid function evolution after reintroduction of amiodarone were investigated: 46 of 172 patients with AIT history needed amiodarone reintroduction. At first AIT episode, the mean age was 62.2 ± 16 years with male gender predominance; 65% of patients were classified as type 1 AIT. AIT recurred in 14 patients (30%), 12 patients developed hypothyroidism (26%), and 20 patients remained euthyroid (44%). Characteristics of type 1 AIT during the first episode, namely briefer exposure period to amiodarone and longer duration of treatment to normalize thyroid hormones, were predictive of AIT recurrence; 73% of patients (8 of 11) with previous episode of type 1 AIT, who did not receive a preventive thioamide treatment, developed a second episode of AIT. Thioamide preventive treatment could be useful to prevent type 1 AIT recurrence. In conclusion, AIT recurrence after amiodarone reintroduction is 4 times more frequent in patients with type 1 AIT history. Thyroid ablation before amiodarone reintroduction in patients with a history of type 1 AIT is preferred. Preventive thioamide treatment could be suggested in patients with type 1 AIT history pending for surgery.

Acute and Chronic Pheochromocytoma-Induced Cardiomyopathies: Different Prognoses?: A Systematic Analytical Review.

Pheochromocytoma and paraganglioma (PPG) are rare and late-diagnosed catecholamine secreting tumors, which may be associated with unrecognized and/or severe cardiomyopathies. We performed a computer-assisted systematic search of the electronic Medline databases using the MESH terms "myocarditis," "myocardial infarction," "Takotsubo," "stress cardiomyopathy," "cardiogenic shock", or "dilated cardiomyopathy," and "pheochromocytoma" or "paraganglioma" from 1961 to August 2012. All detailed case reports of cardiomyopathy due to a PPG, without coronary stenosis, and revealed by acute symptoms were included and analyzed. A total of 145 cases reports were collected (49 Takotsubo Cardiomyopathies [TTC] and 96 other Catecholamine Cardiomyopathies [CC]). At initial presentation, prevalence of high blood pressure (87.7%), chest pain (49.0%), headaches (47.6%), palpitations (46.9%), sweating (39.3%), and shock (51.0%) were comparable between CC and TTC. Acute pulmonary edema (58.3% vs 38.8%, P = 0.03) was more frequent in CC. There was no difference in proportion of patients with severe left ventricular systolic dysfunction (LV Ejection Fraction [LVEF] < 30%) at initial presentation between both groups (P = 0.15). LVEF recovery before (64.9% vs 40.8%, P = 0.005) and after surgical resection (97.7% vs 73.3%, P = 0.001) was higher in the TTC group. Death occurred in 11 cases (7.6%). In multivariate analysis, only TTC was associated with a better LV recovery (0.15 [0.03-0.67], P = 0.03). Pheochromocytoma and paraganglioma can lead to different cardiomyopathies with the same brutal and life-threatening initial clinical presentation but with a different recovery rate. Diagnosis of unexplained dilated cardiomyopathy or TTC should lead clinicians to a specific search for PPG.

A single pathophysiological pathway in Takotsubo cardiomyopathy: Catecholaminergic stress.

BACKGROUND: Takotsubo cardiomyopathy (TTC) continues to be under-diagnosed, due to its varying presentation, with potentially serious consequences if treatment is delayed. AIMS: To demonstrate the consistent involvement of catecholaminergic stress in TTC, regardless of the trigger. METHODS: Between 01 July 2009 and 31 August 2013, patients managed in our centre for thoracic pain syndrome, with or without troponin release, were followed up prospectively. TTC was diagnosed from the apical ballooning seen on left ventricular imaging (angiography or transthoracic echocardiography) in the absence of a significant coronary artery lesion. Triggers (emotional trauma, surgical stress and ß2-mimetic intoxication) were recorded; catecholamine-secreting tumours were screened for with a urinary methoxylate-derivative assay. RESULTS: TTC was diagnosed in 40 out of 2754 (1.5%) patients with thoracic pain syndrome, with or without troponin release. Triggers were emotional trauma (n=29, 72.5%), surgical stress (n=5, 12.5%), adrenergic intoxication (n=3, 7.5%) and catecholaminergic tumour (n=3, 7.5%). Mean left ventricular ejection fraction at admission was 38.0 ± 15.7%. Eight (20%) patients initially showed cardiogenic shock. In-hospital mortality was 7.5%, with no deaths from cardiogenic causes. Thirty-five (94.6%) of the survivors had recovered a normal left ventricular ejection fraction (> 55%) by discharge. CONCLUSION: Whatever the trigger, the common denominator in TTC is catecholaminergic stress. Classically suggested after emotional trauma, TTC may also be induced by surgical stress or endogenous or iatrogenic ß2-mimetic intoxication. The various contexts all have a similarly excellent cardiovascular prognosis if treated early.

Should an implanted defibrillator be considered in patients with vasospastic angina?

UNLABELLED: Vasospastic angina is a frequent and well-recognized pathology with a high risk of life-threatening ventricular arrhythmias and sudden cardiac death. The diagnosis of vasospastic angina requires the combination of clinical and electrocardiographic variables and the results of provocation tests, such as ergonovine administration. Smoking cessation is the first step in the management of vasospastic angina. Optimal medical treatment using calcium-channel blockers and/or nitrate derivatives can provide protection, but life-threatening ventricular arrhythmias may occur despite optimal medical treatment and several years after the start of treatment. In this review, we evaluate the role of implantable defibrillators as a complement to optimal medical management in patients with life-threatening ventricular arrhythmias due to vasospastic angina; this role is not well characterized in the literature or guidelines. We discuss the role of implantable defibrillators in secondary prevention in light of three recent cases managed in our departments and a review of the literature. An implantable defibrillator was implanted in two of the three cases of vasospastic angina with ventricular arrhythmias that we managed. We considered secondary prevention by implantable defibrillator to be justified even in the absence of any obvious risk factor. Ventricular arrhythmias recurred during implantable defibrillator follow-up in the two patients implanted. CONCLUSION: In patients with life-threatening ventricular arrhythmias due to vasospastic angina, an implantable defibrillator should be considered because of the risk of recurrence despite optimal medical management.

Pulmonary arterial systolic pressure and susceptibility to high altitude pulmonary edema.

There is evidence that pulmonary arterial hypertension plays a major role in the occurrence of high altitude pulmonary edema (HAPE). We tested the hypothesis that the pulmonary arterial systolic pressure response to a challenge associated with hypoxia and mild exercise may be considered a predictive factor of HAPE. Pulmonary arterial systolic pressure was measured by Doppler echocardiography in 8 HAPE susceptible (HAPE-S) subjects and 8 HAPE resistant mountaineers (HAPE-R) during a hypoxic exercise challenge established by the French Association for Sport Medicine (Richalet's test). Pulmonary arterial systolic pressure during hypoxic exercise allowed a significant discrimination between the groups, although an overlap of values was observed. When expressed as individual variations from baseline to hypoxic exercise level however, we found a highly significant difference. No overlap was observed between HAPE-R (range: 6.7-18.5 mmHg) and HAPE-S (range: 19.2-30.4 mmHg) groups, with a cut-off value at 19 mmHg. Plasma Vascular Endothelial growth factor (VEGF) and malondialdehyde (MDA) increased in response to hypoxic exercise only in HAPE-S group. Individual increases in pulmonary arterial systolic pressure during hypoxic exercise from basal resting normoxic values seem relevant to estimate HAPE susceptibility when measured during the Richalet's test.

[Aortocoronary bypass, haemodialysis and internal mammary artery steal]. / Pontage aortocoronarien, hémodialyse et vol thoracique interne.

The dramatic occurrence, during haemodialysis sessions, of hemodynamic and cerebral symptoms in a 53-year-old haemodialysed woman with a history of aortocoronary bypass leads to discovery and treatment by percutaneous angioplasty and stenting of a significant stenosis of proximal subclavian artery, ipsilateral to the arteriovenous fistula, with retrograde flow in internal mammary artery graft and vertebral artery. All symptoms resume after interventional radiology. Analysis of literature confirms possibility of coronary artery steal induced by use of the arteriovenous fistula in haemodialysed patients with ipsilateral internal mammary bypass, especially if there is concomitant subclavian artery stenosis, and leading us to discuss the diagnostic and therapeutic implications.

Is direct coronary stenting the best strategy for long-term outcome? Results of the multicentric randomized benefit evaluation of direct coronary stenting (BET) study.

BACKGROUND: Preliminary trials of direct coronary stenting have demonstrated the benefits of this approach. It lowers procedural cost, time, and radiation exposure compared with predilatation. Nevertheless, the long-term outcome after direct stenting remains less well known. METHODS: Between January and September 1999, 338 patients were randomly assigned to either direct stent implantation (DS+, n = 173) or standard stent implantation with balloon predilatation (DS-, n = 165). Clinical follow-up was performed. RESULTS: Baseline characteristics were similar in the 2 groups. Procedural success was achieved in 98.3% of patients assigned to DS+ and 97.5% of patients assigned to DS- (not significant). Clinical follow-up was obtained in 99% of patients (mean 16.4 +/- 4.6 months). Major adverse cardiac events--defined as whichever of the following occurred first; cardiac death, myocardial infarction, unstable angina, new revascularization--were observed at a higher rate in the DS+ group than in the DS-, but this difference was not significant (11.3% vs 18.2%, P = not significant). The difference in target lesion revascularization rate in the DS+ group (7%) and DS- group (5.2%) was also not significant. Multivariate analysis showed that direct stenting had no influence on long-term major adverse cardiac events rate. Independent relationships were found between long-term major adverse cardiac events rate and final minimal lumen diameter <2.48 mm (relative risk [RR] 0.449, CI 0.239-0.845, P =.013), prior myocardial infarction (RR 2.028, CI 1.114-3.69, P =.02), and hypertension (RR 1.859, CI 1.022-3.383, P =.042). CONCLUSION: The main finding that emerges from this randomized study is that the influence of direct stenting on long-term need for new target lesion revascularization does not differ from that of stenting with balloon predilatation.