[Cardiac manifestations of sickle cell anemia]

HEMOGLOBINS S AND C: Drepanocytosis, the occurrence of sickle cells (drepanocytes) in the blood, is an inherited condition. Electrophoresis demonstrates hemoglobin SS in homozygous subjects who present the typical clinical features of severe hemolytic sickle-cell anemia. Heterozygous subjects have sickle-cell anemia trait, an asymptomatic condition associated with a 50% hemoglobin S and 50% hemoglobin C at electrophoresis. Hemoglobin S and C are transmitted by Mendelian inheritance. CARDIAC DISORDERS: Well-known, cardiac disorders occur in more than 82% of homozygous subjects while only 2% of heterozygous subjects are affected. Heart murmur, radiological cardiomegaly, or eletrocardiographic anomalies are often the only signs. There is a risk of fatal heart failure in children and neonates. Acute rheumatic fever or infectious endocarditis, particularly due to pneumococcal or Haemophilus influenzae infection, may trigger heart failure. CARDIAC ANOMALIES: Patients with sickle-cell anemia can develop an "anemic heart" expressed by an elevated cardiac output and systemic ejection volume at rest and a fall in arteriolar peripheral resistance. Patients who develop cor pulmonae have an elevated pulmonary pressure at exercise and experience venous occlusive events with a progressive reduction in the pulmonary vascular bed and development of a left-right shunt. Myocardiopathy leads to left ventricular dysfunction contrasting with the dilated right heart seen at echocardiography and rare cases of transmural infarction.

Double heterozygosity for mutations in the beta-myosin heavy chain and in the cardiac myosin binding protein C genes in a family with hypertrophic cardiomyopathy

Familial hypertrophic cardiomyopathy is a genetically heterogeneous autosomal dominant disease, caused by mutations in several sarcomeric protein genes. So far, seven genes have been shown to be associated with the disease with the beta-myosin heavy chain (MYH7) and the cardiac myosin binding protein C (MYBPC3) genes being the most frequently involved. We performed electrocardiography (ECG) and echocardiography in 15 subjects with hypertrophic cardiomyopathy from a French Caribbean family. Genetic analyses were performed on genomic DNA by haplotype analysis with microsatellite markers at each locus involved and mutation screening by single strand conformation polymorphism analysis. Based on ECG and echocardiography, eight subjects were affected and presented a classical phenotype of hypertrophic cardiomyopathy. Two new mutations cosegregating with the disease were found, one located in the MYH7 gene exon 15 (Glu483Lys) and the other in the MYBPC3 gene exon 30 (Glu1096 termination codon). Four affected subjects carried the MYH7 gene mutation, two the MYBPC3 gene mutation, and two were doubly heterozygous for the two mutations. The doubly heterozygous patients exhibited marked left ventricular hypertrophy, which was significantly greater than in the other affected subjects. We report for the first time the simultaneous presence of two pathological mutations in two different genes in the context of familial hypertrophic cardiomyopathy. This double heterozygosity is not lethal but is associated with a more severe phenotype.

[Venous thromboembolic complications following air travel. Retrospective study of 40 cases recorded in Martinique]

Thromboembolic events following air travel do occur, and have been reported several times in the literature. The authors report a high frequency of these incidence in their geographical region. A retrospective study of 40 cases of phlebitis or pulmonary embolism associated with air travel was conducted over the last 6 years. Cases were analyzed based on the following criteria: sex, age, duration of flight, latency period, diagnostic signs, way of discovery, date of diagnosis and thrombus localisation. The authors analyse these data and underline the main causes of these incidence, with an emphasis on the specific climatic factors in their region. Special attention is placed on the fact that these may occur in young individuals with no previous medical history. The authors conclude by suggesting preventive measures, including general measures and the use of anticoagulants.

[Congenital coronary-cardiac fistula. Diagnosis by color Doppler echocardiography in an infant]

The authors report the case of a 2 month old child in whom a coronary artery fistulae was diagnosed by colour Doppler echocardiography. Routine two-dimensional echocardiography showed a very dilated right coronary artery. Turbulent flow was detected in this vessel by pulsed Doppler echocardiography. Colour Doppler showed the fistulous connection to the inferior wall of the right ventricle. Until recently, this condition could only be diagnosed by selective angiography and coronary arteriography. Although there have been few reports in the literature, colour Doppler echocardiography would seem to be a significant advance in non-invasive diagnosis of abnormal connections of the coronary arteries. It allows the differential diagnosis of coronary aneurysm, ectopic coronary arteries and sinus of Valsalva aneurysms to be excluded. The patients can be followed up by colour Doppler echocardiography and anatomic information can be obtained to guide surgery, notably the site of drainage of the fistula. Coronary artery fistulae presenting clinically with a continuous murmer atypically situated for a patent ductus arteriosus are difficult to detect by conventional echocardiography and usually required cardiac catheterisation and angiography. Color Doppler echocardiography is a valuable non invasive diagnostic tool for this condition. The others report the case of a coronary artery cardiac fistula in a neonate diagnosed by color Doppler echocardiography.

[Left ventricule function and sickle-cell anemia. Echocardiographic study]

The dimensions of the cardiac chambers and left ventricular function were studied by echocardiography in 40 patients with homozygous sickle cell disease (SS) and 25 patients with heterozygous sickle cell trait (12 AS, 10 SC, 3 BS) and compared with the same parameters in 30 normal subjects. Patients with homozygous SS disease had significantly larger left atrial (32.2 +/- 6.47 mm vs 26.62 +/- 5.64 mm; p less than 0.001), left ventricular (46.4 +/- 8.49 mm vs 39.97 +/- 5.29 mm; p less than 0.001) and right ventricular (17.95 +/- 5.08 mm vs 15.5 +/- 3.17 mm; p less than 0.02) dimensions: they also had higher indexed myocardial surfaces (11.48 +/- 2.36 cm2/m2 vs 8.21 +/- 1.97 cm2/m2; p less than 0.001) and indexed end diastolic left ventricular volumes (101.84 +/- 22.74 ml/m2 vs 65.05 +/- 10.81 ml/m2; p less than 0.001), a higher cardiac index (4.77 +/- 1.33 l/mn/m2 vs 3.58 +/- 1.08 l/mn/m2; p less than 0.001) and stroke volume (71.77 +/- 32.86 ml vs 49.56 +/- 13.39 ml; p less than 0.001). Peripheral resistances were significantly lower (1341 +/- 469 vs 1626 +/- 368 dynes/s/cm-5; p less than 0.01) as were the velocities of circumferential fibre shortening (VCF) (1.11 +/- 0.20 circ/s vs 1.28 +/- 0.24 circ/s; p less than 0.01). Two thirds of homozygous SS disease patients (27/40) had appearances of an anaemic heart with eccentric left ventricular hypertrophy, normal left ventricular systolic function, an increased cardiac index (5.01 +/- 1.19 l/mn/m2) and low peripheral arterial resistances.(ABSTRACT TRUNCATED AT 250 WORDS)

[Congenital diverticulum of the right ventricle apropos of a case complicated by pulmonary endocarditis]

Congenital diverticulum of the right ventricle is an extremely rare abnormality, usually discovered by chance during evaluation of a more complex cardiac malformation. We report a case of isolated diverticulum of the right ventricle in a 14-year old boy who also had pulmonary valve endocarditis secondary to acute osteomyelitis. Owing to the evolutive risks inherent in the diverticulum and to the persistence of highly mobile pulmonary valve vegetations 5 years after the initial infectious episode, surgical treatment of the lesions had to be performed. The diagnostic, evolutive and therapeutic problems raised by right ventricular diverticula are discussed.

[Bouillaud's disease in Martinique. Epidemiological and nosological features]

From the epidemiological point of view there does not appear to be any particular geographical pattern of this disease. Indeed, it is poor living conditions, low family income, large family size and poor oro-dental hygiene which are responsable for the outbreak of small familial epidemics of acute rheumatic disease of the joints; from the clinical point of view, acute rheumatic joint disease presents no particular features in the Antilles. All the characteristics described in the classical works are found, including the malignant form, whose rarity is emphasised. A programme of prevention of rheumatic disease has yet to be started in the Antilles, and we feel that it should be a three-pronged attack: 1. More information to the general public on the necessity for rapid treatment of the symptoms; 2. Increased vigilance by the medical services in the fight against this disease of deprivation, and close collaboration with the social services; 3. Finally, the setting up of a specialised social cardiology service to supervise the young rheumatic patients, and to ensure that they are educated. Such arrangements would avoid the disorganisation sometimes experienced by the families and friends; it must be admitted that we sometimes have to prevail upon the family to allow the child to be transferred to a centre of social cardiology on the continent so that the young rheumatic patient may receive training for a career which is compatible with his or her handicap.