State-of-the art review: Noncompaction cardiomyopathy in pediatric patients

Heart Failure Reviews - Noncompaction cardiomyopathy (NCCM) is a disease characterized by hypertrabeculation, commonly hypothesized due to an arrest in compaction during fetal development. In 2006,...     

Blood volume and body fluid compartments in lambs with aortopulmonary left-to-right shunts.

A left-to-right shunt is accompanied by an increased plasma and blood volume. Since this is likely realized through renin/aldosterone-mediated salt and water retention, other body fluid compartments may be changed too. Therefore, we studied blood volume and body fluid compartments by a single-injection, triple-indicator dilution technique in nine 8-wk-old lambs with an aortopulmonary left-to-right shunt (55 +/- 3% of left ventricular output; mean +/- SEM) and in 11 control lambs, 2.5 wk after surgery. Systemic blood flow was maintained at the same level as in control lambs, but the aortic pressure of the shunt lambs was lower. Blood volume in shunt lambs was larger than in control lambs (110 +/- 6 vs. 84 +/- 7 ml/kg, P < 0.001) through an increase in plasma volume, which correlated significantly with the magnitude of the left-to-right shunt (r = 0.81, P < 0.01). Red blood cell volume was equal to that of control lambs. Evidence was obtained that the increase in plasma volume was induced by a transient increase in renin (8.0 +/- 2.2 vs. 1.6 +/- 0.2 nmol.l-1.h-1; P < 0.02) and aldosterone (0.51 +/- 0.14 vs. 0.24 +/- 0.09 nmol/liter) concentrations. Interstitial water volume, however, was not significantly different from that in control lambs. The amount of intravascular protein was significantly higher than in control lambs (5.0 +/- 0.3 vs. 3.5 +/- 0.2 g/kg body mass, P < 0.001). There were no significant differences in intracellular and total body water volumes between the two groups. We conclude that the increased amount of intravascular protein confines the fluid retained by the kidneys to the vascular compartment.     

In utero ventilation augments the left ventricular response to isoproterenol and volume loading in fetal sheep

In its normal circulatory environment, the fetal left ventricle can maximally increase output less than 2-fold, in contrast to the nearly 3-fold increase that occurs at birth. Several studies have attributed this finding to fetal myocardial "immaturity," and speculated that there is a rapid maturation of the myocardium in the perinatal period. We investigated the importance of the circulatory environment itself, rather than myocardial immaturity, by measuring left ventricular output (LVO) during in utero oxygen ventilation and isoproterenol infusion. We studied seven near-term fetal sheep greater than or equal to 2 d after placement of intravascular catheters, an endotracheal tube, and an electromagnetic flow transducer around the ascending aorta. We measured hemodynamic variables in the presence and absence of all combinations of oxygen ventilation, isoproterenol infusion, and volume infusion. Baseline LVO was normal (133 +/- 27 mL.kg-1.min-1). Individually, oxygen ventilation (136 +/- 11 mL.kg-1.min-1, p less than 0.001) and isoproterenol (48 +/- 11 mL.kg-1.min-1, p less than 0.05) increased LVO significantly; volume infusion did not. Their cumulative effect increased LVO nearly 3-fold (to 387 +/- 98 mL.kg-1.min-1), similar to levels seen in the newborn lamb. Mean left atrial pressure increased above right during oxygen ventilation (from 0.05 +/- 0.54 kPa to 0.82 +/- 0.39 kPa, p less than or equal to 0.0001). We conclude that the previously observed limitation in maximal LVO in the near-term fetus is primarily caused by its circulatory environment rather than relative myocardial immaturity, and speculate that a prominent Starling response is uncovered by decreases in left ventricular afterload and right ventricular constraint.     

Myocardial carbohydrate, ketone, and fatty acid uptake in conscious lambs with aortopulmonary shunts.

A left to right shunt increases myocardial work and is often accompanied by increased catecholamine levels. Because both increased myocardial work and increased catecholamine levels may induce increased fatty acid utilization, which could increase resting myocardial oxygen consumption and therefore unfavorably affect coronary reserve, we studied myocardial uptake of glucose, pyruvate, lactate, beta-OH-butyrate, acetoacetate, FFA, and triglycerides in 12 7-wk-old lambs with aortopulmonary left to right shunts (58 +/- 2% of left ventricular output, mean +/- SEM) and in 10 control lambs 2 wk after surgery. Despite the shunt, systemic blood flow in the shunt lambs was maintained at the same level as in the control lambs. This was accomplished by an increased heart rate and stroke volume. Furthermore, the shunt was accompanied by an increased myocardial oxygen consumption in the shunt lambs (834 +/- 70 versus 528 +/- 43 mumol O2.min-1 x 100 g-1; p less than 0.05). There were no significant differences in arterial substrate concentrations between the two groups. The same was true for arteriovenous differences across the myocardium, with the exception of lactate, which was substantially higher in shunt than in control lambs (72 +/- 25 versus 18 +/- 23 mumol/L; p less than 0.05). As a consequence, myocardial lactate uptake in the shunt lambs was increased 15-fold (18 +/- 6 versus 1 +/- 2 mumol.min-1 x 100 g-1; p less than 0.02), whereas uptake of the other substrates merely paralleled the increased myocardial blood flow.(ABSTRACT TRUNCATED AT 250 WORDS)     

Cardiac Phenotypes,Genetics, and Risks in Familial Noncompaction Cardiomyopathy

Background

There is overlap in genetic causes and cardiac features in noncompaction cardiomyopathy (NCCM), hypertrophic cardiomyopathy (HCM), and dilated cardiomyopathy (DCM).

Undetected chronic obstructive pulmonary disease and asthma in people over 50 years with persistent cough

Background

Chronic obstructive pulmonary disease (COPD) and asthma are underdiagnosed in primary care.

Aim

To determine how often COPD or asthma are present in middle-aged and older patients who consult their GP for persistent cough.

Design of study

A cross-sectional study in 353 patients older than 50 years, visiting their GP for persistent cough and not known to have COPD or asthma.

Setting

General practice in the Netherlands.

Method

All participants underwent extensive diagnostic work-up, including symptoms, signs, spirometry, and body plethysmography. All results were studied by an expert panel to diagnose or exclude COPD and/or asthma. The reproducibility of the panel diagnosis was assessed by calculation of Cohen''s κ statistic in a sample of 41 participants.

Results

Of the 353 participants, 102 (29%, 95% confidence interval [CI] = 24 to 34%) were diagnosed with COPD. In 14 of these 102 participants, both COPD and asthma were diagnosed (4%, 95% CI = 2 to 7%). Asthma (without COPD) was diagnosed in 23 (7%, 95% CI = 4 to 10%) participants. Mean duration of cough was 93 days (median 40 days). The reproducibility of the expert panel was good (Cohen''s κ = 0.90).

Conclusion

In patients aged over 50 years who consult their GP for persistent cough, undetected COPD or asthma is frequently present.     

Neonatal pulmonary arteriovenous malformation in hereditary haemorrhagic telangiectasia

A 3 week old infant presented with persistent hypoxaemia and was diagnosed with pulmonary arteriovenous malformations. Her family history was positive for hereditary haemorrhagic telangiectasia. She was treated successfully with coil embolotherapy at the age of 4 months. Transcatheter embolisation may be considered the primary treatment for pulmonary arteriovenous malformations in infancy.