Nicholas A. McKeag

The Role of Micronutrients in Heart Failure

Heart failure is a common condition in the Western world, particularly among elderly persons and with an ever-aging population, the incidence is expected to increase. Diet in the setting of heart failure is important--patients with this condition are advised to consume a low-salt diet and monitor their weight closely. Nutritional status of patients with heart failure also is important--those with poor nutritional status tend to have a poor long-term prognosis. A growing body of evidence suggests an association between heart failure and micronutrient status. Reversible heart failure has been described as a consequence of severe thiamine and selenium deficiency. However, contemporary studies suggest that a more subtle relationship may exist between micronutrients and heart failure. This article reviews the existing literature linking heart failure and micronutrients, examining studies that investigated micronutrient intake, micronutrient status, and the effect of micronutrient supplementation in patients with heart failure, and focusing particularly on vitamin A, vitamin C, vitamin E, thiamine, other B vitamins, vitamin D, selenium, zinc, and copper.

Insulation Failure of the Linox Defibrillator Lead: A Case Report and Retrospective Review of a Single Center Experience.

Implantable cardioverter defibrillator (ICD) lead insulation failure and conductor externalization have been increasingly reported. The 7.8F silicon‐insulated Linox SD and Linox S ICD leads (Biotronik, Berlin, Germany) were released in 2006 and 2007, respectively, with an estimated 85,000 implantations worldwide. A 39‐year‐old female suffered an out‐of‐hospital ventricular fibrillation (VF) arrest with successful resuscitation. An ICD was implanted utilizing a single coil active fixation LinoxSmart S lead (Biotronik, Berlin, Germany). A device‐triggered alert approximately 3 years after implantation confirmed nonphysiological high rate sensing leading to VF detection. A chest X‐ray showed an abnormality of the ICD lead and fluoroscopic screening confirmed conductor externalization proximal to the defibrillator coil. In view of the combined electrical and fluoroscopic abnormalities, urgent lead extraction and replacement were performed. A review of Linox (Biotronik) and Vigila (Sorin Group, Milan, Italy) lead implantations within our center (n = 98) identified 3 additional patients presenting with premature lead failure, 2 associated with nonphysiological sensed events and one associated with a significant decrease in lead impedance. All leads were subsequently removed and replaced. This case provides a striking example of insulation failure affecting the Linox ICD lead and, we believe, is the first to demonstrate conductor externalization manifesting both electrical and fluoroscopic abnormalities.

The Effect of Multiple Micronutrient Supplementation on Left Ventricular Ejection Fraction in Patients With Chronic Stable Heart Failure : A Randomized, Placebo-Controlled Trial

OBJECTIVES This study sought to investigate the effect of a multiple micronutrient supplement on left ventricular ejection fraction (LVEF) in patients with heart failure. BACKGROUND Observational studies suggest that patients with heart failure have reduced intake and lower concentrations of a number of micronutrients. However, there have been very few intervention studies investigating the effect of micronutrient supplementation in patients with heart failure. METHODS This was a randomized, double-blind, placebo-controlled, parallel-group study involving 74 patients with chronic stable heart failure that compared multiple micronutrient supplementation taken once daily versus placebo for 12 months. The primary endpoint was LVEF assessed by cardiovascular magnetic resonance imaging or 3-dimensional echocardiography. Secondary endpoints were Minnesota Living With Heart Failure Questionnaire score, 6-min walk test distance, blood concentrations of N-terminal prohormone of brain natriuretic peptide, C-reactive protein, tumor necrosis factor alpha, interleukin-6, interleukin-10, and urinary levels of 8-iso-prostaglandin F2 alpha. RESULTS Blood concentrations of a number of micronutrients increased significantly in the micronutrient supplement group, indicating excellent compliance with the intervention. There was no significant difference in mean LVEF at 12 months between treatment groups after adjusting for baseline (mean difference: 1.6%, 95% confidence interval: -2.6 to 5.8, p = 0.441). There was also no significant difference in any of the secondary endpoints at 12 months between treatment groups. CONCLUSIONS This study provides no evidence to support the routine treatment of patients with chronic stable heart failure with a multiple micronutrient supplement. (Micronutrient Supplementation in Patients With Heart Failure [MINT-HF]; NCT01005303).

Fluoroscopic and Electrical Assessment of Implantable Cardioverter Defibrillator Leads: A Prospective Observational Study

Insulation defects resulting in conductor externalization (CE) have been reported in the Riata family of implantable cardioverter defibrillator (ICD) leads (St. Jude Medical, Sylmar, CA, USA). The aim of this study was to identify, prospectively, the rate of CE and outcomes following this, within a group of patients with a Riata ICD lead.

Dietary Micronutrient Intake and Micronutrient Status in Patients With Chronic Stable Heart Failure: An Observational Study.

Background: Observational studies suggest that patients with heart failure have a tendency to a reduced status of a number of micronutrients and that this may be associated with an adverse prognosis. A small number of studies also suggest that patients with heart failure may have reduced dietary intake of micronutrients, a possible mechanism for reduced status. Objective: The aims of this study were to assess dietary micronutrient intake and micronutrient status in a group of patients with heart failure. Methods: Dietary intake was assessed in 79 outpatients with chronic stable heart failure with a reduced ejection fraction using a validated food frequency questionnaire. Blood concentrations of a number of micronutrients, including vitamin D, were measured in fasting blood samples, drawn at the time of food frequency questionnaire completion. Results: More than 20% of patients reported intakes less than the reference nutrient intake or recommended intake for riboflavin, vitamin D, vitamin A, calcium, magnesium, potassium, zinc, copper, selenium, and iodine. More than 5% of patients reported intakes less than the lower reference nutrient intake or minimum recommended intake for riboflavin, vitamin D, vitamin A, calcium, magnesium, potassium, zinc, selenium, and iodine. Vitamin D deficiency (plasma total 25-hydroxy-vitamin D concentration <50 nmol/L) was observed in 75.6% of patients. Conclusions: Vitamin D deficiency was common in this group of patients with heart failure. Based on self-reported dietary intake, a substantial number of individuals may not have been consuming enough vitamin D and a modest number of individuals may not have been consuming enough riboflavin, vitamin A, calcium, magnesium, potassium, zinc, copper, selenium, or iodine to meet their dietary needs.

Pneumopericardium after Permanent Pacemaker Implantation

An 87-year-old man presented at the hospital with shortness of breath and syncope. His medical history included ischemic heart disease, emphysema, and hypertension. An electrocardiogram showed complete heart block and nonsustained polymorphic ventricular tachycardia. A temporary ventricular pacing wire was inserted. In the coronary care unit, the patient was treated for a community-acquired chest infection. A dual-chamber permanent pacemaker (PPM) was inserted by means of left cephalic vein cutdown. Active-fixation leads were used. After implantation, a device check, lead check, and chest radiograph revealed nothing abnormal. Eight days later, the patient had dyspnea and hemoptysis. A chest radiograph showed patchy consolidation in the lower zone of both lung fields, the right atrial pacing leads tip situated outside the cardiac silhouette, and evidence of pneumopericardium (Fig. 1). At the regional cardiology center, the right atrial pacing lead was uneventfully removed and replaced with a passive-fixation lead. The patient was discharged from the center 3 days later. Fig. 1 Chest radiograph shows an extracardiac location of the right atrial pacing lead tip (arrow) and pneumopericardium. The arrowhead indicates the pericardial outline.

Lipomatous metaplasia within an old anterior myocardial infarction

A 54-year-old gentleman with a history of anterior myocardial infarction (MI) in 2000 and inferior MI in 2004 attended for a cardiovascular magnetic resonance (CMR) scan. Steady-state free precession (SSFP) imaging revealed a severely dilated left ventricle with severe impairment of systolic function. Significant thinning was noted in the apical anteroseptal and mid to basal inferolateral regions in keeping with previous MI in these territories. In addition, an area of high …

Thrombus formation on a defibrillator lead with conductor externalization.

A 51 year old man with arrhythmogenic right ventricular cardiomyopathy reported non-specific symptoms of muscle aches and shivering at outpatient review. A dual chamber implantable cardioverter defibrillator (ICD) had been inserted seven years previously. Fluoroscopic lead screening had previously demonstrated conductor externalisation (Figure and Video) of a single coil Riata ICD lead (model number 1582-65, St. Jude Medical, Sylmar, CA, USA). All electrical parameters were normal. Supplementary data related to this article can be found online at http://dx.doi.org/10.1016/j.ipej.2015.07.014.

The effect of multiple micronutrient supplementation on left ventricular ejection fraction in patients with chronic stable heart failure: a randomized, placebo-controlled trial: A randomized, placebo-controlled trial

OBJECTIVES This study sought to investigate the effect of a multiple micronutrient supplement on left ventricular ejection fraction (LVEF) in patients with heart failure. BACKGROUND Observational studies suggest that patients with heart failure have reduced intake and lower concentrations of a number of micronutrients. However, there have been very few intervention studies investigating the effect of micronutrient supplementation in patients with heart failure. METHODS This was a randomized, double-blind, placebo-controlled, parallel-group study involving 74 patients with chronic stable heart failure that compared multiple micronutrient supplementation taken once daily versus placebo for 12 months. The primary endpoint was LVEF assessed by cardiovascular magnetic resonance imaging or 3-dimensional echocardiography. Secondary endpoints were Minnesota Living With Heart Failure Questionnaire score, 6-min walk test distance, blood concentrations of N-terminal prohormone of brain natriuretic peptide, C-reactive protein, tumor necrosis factor alpha, interleukin-6, interleukin-10, and urinary levels of 8-iso-prostaglandin F2 alpha. RESULTS Blood concentrations of a number of micronutrients increased significantly in the micronutrient supplement group, indicating excellent compliance with the intervention. There was no significant difference in mean LVEF at 12 months between treatment groups after adjusting for baseline (mean difference: 1.6%, 95% confidence interval: -2.6 to 5.8, p = 0.441). There was also no significant difference in any of the secondary endpoints at 12 months between treatment groups. CONCLUSIONS This study provides no evidence to support the routine treatment of patients with chronic stable heart failure with a multiple micronutrient supplement. (Micronutrient Supplementation in Patients With Heart Failure [MINT-HF]; NCT01005303).

The Effect of Multiple Micronutrient Supplementation on Left Ventricular Ejection Fraction in Patients With Chronic Stable Heart Failure

OBJECTIVES This study sought to investigate the effect of a multiple micronutrient supplement on left ventricular ejection fraction (LVEF) in patients with heart failure. BACKGROUND Observational studies suggest that patients with heart failure have reduced intake and lower concentrations of a number of micronutrients. However, there have been very few intervention studies investigating the effect of micronutrient supplementation in patients with heart failure. METHODS This was a randomized, double-blind, placebo-controlled, parallel-group study involving 74 patients with chronic stable heart failure that compared multiple micronutrient supplementation taken once daily versus placebo for 12 months. The primary endpoint was LVEF assessed by cardiovascular magnetic resonance imaging or 3-dimensional echocardiography. Secondary endpoints were Minnesota Living With Heart Failure Questionnaire score, 6-min walk test distance, blood concentrations of N-terminal prohormone of brain natriuretic peptide, C-reactive protein, tumor necrosis factor alpha, interleukin-6, interleukin-10, and urinary levels of 8-iso-prostaglandin F2 alpha. RESULTS Blood concentrations of a number of micronutrients increased significantly in the micronutrient supplement group, indicating excellent compliance with the intervention. There was no significant difference in mean LVEF at 12 months between treatment groups after adjusting for baseline (mean difference: 1.6%, 95% confidence interval: -2.6 to 5.8, p = 0.441). There was also no significant difference in any of the secondary endpoints at 12 months between treatment groups. CONCLUSIONS This study provides no evidence to support the routine treatment of patients with chronic stable heart failure with a multiple micronutrient supplement. (Micronutrient Supplementation in Patients With Heart Failure [MINT-HF]; NCT01005303).