Biomedical subjects

Mark Haigney

Publications and source records attributed to Mark Haigney.

5 recordsLinked to original sources

PubMed2006

Diuretic use, progressive heart failure, and death in patients in the DIG study.

BACKGROUND: Nonpotassium-sparing diuretics (NPSDs), have been associated with increased sudden cardiac death (SCD) and progressive heart failure (HF) death in HF patients. METHODS AND RESULTS: In 6797 Digitalis Investigation Group study patients, risk ratios were calculated for death, cardiovascular death (CVD), death from worsening HF, SCD, and HF hospitalization among those taking a potassium-sparing (PSD), NPSD, or no diuretic. Compared with not taking diuretic, risk of death (relative risk [RR] 1.36, 95% confidence interval [CI] 1.17-1.59, P < .0001), CVD (RR = 1.38, 95% CI 1.17-1.63, P = .0001), progressive HF death (RR = 1.41, 95% CI 1.06-1.89, P = .02), SCD (RR = 1.67, 95% CI 1.23-2.27, P = .001), and HF hospitalization (RR = 1.68, 95% CI 1.41-1.99, P < .0001) were increased with NPSD. There was no significant difference in any end point for patients taking only PSD compared to no diuretic. PSD only subjects were less likely than NPSD subjects to be hospitalized for HF (RR = 0.71, 95% CI 0.52-0.96, P = .02). CONCLUSION: NPSDs are associated with increased risk of death, CVD, progressive HF death, SCD, and HF hospitalization. A randomized trial is needed to assess the role of NPSDs versus PSDs in HF patients.

Aged↗

PubMed2005

Potassium, magnesium, and electrolyte imbalance and complications in disease management.

Electrolyte balance is a critical issue in managing comorbid conditions in both diseased and elderly patients. Patients with hypertension and diabetes need careful regulation of their calcium and magnesium levels, whereas in patients with congestive heart failure, sodium and potassium levels also are critical. Herein we report the outcome of a round table discussion at which issues of renal magnesium clearance, magnesium and arrhythmic risk, ion balance in heart failure, diabetes, ischemic stress, oxidative stress in the cardiomyopathy of magnesium deficiency, roles of magnesium and potassium in bone metabolism and the aging population, and the role of electrolyte balance in hypertension have been discussed. In all these issues the maintaining homeostasis of potassium and magnesium is critical and the various therapies that impact on retaining these ions were discussed. Hallmark studies, i.e., Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial and Studies of Left Ventricular Dysfunction, have provided insight into treatment of patients with cardiovascular and progressive heart failure. These studies and the availability of potassium- and magnesium-sparing diuretics for use in these disorders provide relevant perspectives for treatment.

Diabetes Complications↗

PubMed2005

Symptomatic pericardial constriction without active pericarditis.

The decision to undergo pericardectomy for symptomatic pericardial constriction is usually dictated by an image of an abnormal pericardium. We report a case of symptomatic pericardial constriction despite radiographic and pathological evidence of a normal pericardium. The patient was successfully treated with a pericardectomy, with resolution of constrictive hemodynamics and symptoms. Our report suggests that a normal pericardium by computed tomography and biopsy should not preclude pericardectomy for patients who have refractory symptoms, physical findings, and intracardiac pressures diagnostic of constrictive pericarditis.

Aged↗

PubMed2003

Diuretic use, progressive heart failure, and death in patients in the Studies Of Left Ventricular Dysfunction (SOLVD).

OBJECTIVES: We sought to determine whether non-potassium-sparing diuretics (PSDs) in the absence of a PSD may result in progressive heart failure (HF). BACKGROUND: Angiotensin-converting enzyme (ACE) inhibitors incompletely suppress ACE activity in HF patients. Furthermore, non-PSDs are activators of aldosterone secretion. We reasoned that non-PSDs, in the absence of a PSD, might result in progressive HF. METHODS: In the 6,797 patients in the Studies Of Left Ventricular Dysfunction (SOLVD), we compared the risk of hospitalization for, or death from, HF between those taking a PSD and those who were not, adjusting for known covariates. RESULTS: The risk of hospitalization from worsening HF in those taking a PSD relative to those taking only a non-PSD was 0.74 (95% confidence interval [CI] 0.55 to 0.99; p = 0.047). The relative risk for cardiovascular death was 0.74 (95% CI 0.59 to 0.93; p = 0.011), for death from all causes 0.73 (95% CI 0.59 to 0.90; p = 0.004), and for hospitalization for, or death from, HF 0.75 (95% CI 0.58 to 0.97; p = 0.030). Compared with patients not taking any diuretic, the risk of hospitalization or death due to worsening HF in patients taking non-PSDs alone was significantly increased (risk ratio [RR] = 1.31, 95% CI 1.09 to 1.57; p = 0.0004); this was not observed in patients taking PSDs with or without a non-PSD (RR = 0.99, 95% CI 0.76 to 1.30; p = 0.95). CONCLUSIONS: The use of PSDs in HF patients is associated with a reduced risk of death from, or hospitalization for, progressive HF or all-cause or cardiovascular death, compared with patients taking only a non-PSD.

Aged↗

PubMed2002

Predisposition to arrhythmia and autonomic dysfunction in Nhlh1-deficient mice.

Nhlh1 is a basic helix-loop-helix transcription factor whose expression is restricted to the nervous system and which may play a role in neuronal differentiation. To directly study Nhlh1 function, we generated null mice. Homozygous mutant mice were predisposed to premature, adult-onset, unexpected death. Electrocardiograms revealed decreased total heart rate variability, stress-induced arrhythmia, and impaired baroreceptor sensitivity. This predisposition to arrhythmia is a likely cause of the observed death in the mutant mice. Heterozygosity for the closely related transcription factor Nhlh2 increased the severity of the Nhlh1-null phenotype. No signs of primary cardiac structural or conduction abnormalities could be detected upon necropsy of the null mice. The pattern of altered heart rhythm observed in basal and experimental conditions (stress and pharmacologically induced) suggests that a deficient parasympathetic tone may contribute to the arrhythmia in the Nhlh1-null mouse. The expression of Nhlh1 in the developing brain stem and in the vagal nuclei in the wild-type mouse further supports this hypothesis. The Nhlh1 mutant mouse may thus provide a model to investigate the contribution of the autonomic nervous system to arrhythmogenesis.

Animals↗