This report documents, for the first time, that a homoplasmic mitochondrial tRNA mutation may cause maternally inherited HCM. It highlights the significant contribution that homoplasmic mitochondrial tRNA substitutions may play in the development of cardiac disease. A restriction of the biochemical defect to the affected tissue has important implications for the screening of patients with cardiomyopathy for mitochondrial disease.

DiGeorge syndrome was diagnosed in an infant who had an interrupted aortic arch, hypoparathyroidism, and low T lymphocyte numbers. Two siblings had heart defects that are not commonly described in DiGeorge syndrome (a membranous ventricular septal defect and coarctation of the aorta respectively). These siblings did not have evidence of thymic dysfunction or hypoparathyroidism.Chromosome analysis showed that the mother, whose cardiovascular examination was normal, and her three offspring with heart defects had a 22qll interstitial deletion, which was confirmed by molecular analysis.This family suggests that 22qll deletions can cause apparently isolated heart defects and that the range of these defects may be wider than previously recognised. Once the genes that are deleted in this family are characterised they will be useful candidate genes in the investigation of isolated cardiac malformations.

was reviewed and linear calcification was detected in both axillary arteries and the descending aorta. A biopsy specimen of the posterior tibial artery showed calcium deposition within the internal elastic lamina and confirmed the diagnosis of idiopathic infantile arterial calcification. Further investigation showed a low plasma concentration of pyrophosphate (0-6 umol/l (normal range in adults 1-6 yumol/l)) but other investigations including blood film; thyroid function tests; serum immunoglobulins; autoantibodies; TORCH (toxoplasma, rubella, cytomegalovirus, and herpes virus) screen; serum parathormone; plasma calcium, phosphate and magnesium; serum alkaline phosphatase; plasma cholesterol and triglycerides; liver function tests; urine aminoacids, mucopolysaccharides, and excretion of calcium and hydroxyprolene were all normal. Over the next 48 hours the infant required an exchange transfusion for haemolytic jaundice though there was no evidence of blood group incompatability or sepsis. After this, treatment with chlorothiazide and spironolactone was started and her cardiac failure and hepatosplenomegaly gradually regressed. Then treatment with disodium etidronate (20 mg three times a day) was started, and by four weeks of age her hepatosplenomegaly had resolved and she was gaining weight. At six weeks the dose of disodium etidronate was reduced to 11 mg three times a day and treatment with diuretics was stopped.At 11 weeks she presented with screaming episodes (probably angina pectoris) and acute heart failure with electrocardiographic evidence of inferolateral myocardial ischaemia. Shortly after admission she suffered a cardiac arrest and resuscitation was unsuccessful. At necropsy the coronary arteries were grossly narrowed by widespread endarteritis and there was extensive calcium deposition between the muscular and subintimal layers. PATIENT 2 Five years later the mother again became pregnant. Serial fetal echocardiography showed the development of a pericardial effusion and calcification of the great vessels by 33 weeks' gestation (fig 1). In view of the developing calcification and hydramnios, labour was induced at 35 weeks. When fetal distress developed an emergency caesarean section was carried out and a male infant (2680 g) was delivered. On examination both radial pulses were absent and the child was tachypnoeic. Chest and abdominal x rays 156 on 12 May 2018 by guest. Protected by copyright.

SUMMARY Fifteen patients aged 1-19 years (mean 10 9) with previously unoperated aortic coarctation underwent percutaneous balloon angioplasty between January 1985 and February 1986. Nine (60%) were hypertensive at presentation. Under general anaesthetic the systolic coarctation gradient was 24-50 mm Hg (mean 29) and the coarctation diameter was 4-9 mm (mean 5 5). Meditech balloon catheters 8-18 mm in diameter were inflated 1-4 times at 410-760 kPa. After dilatation the systolic coarctation gradient decreased to 0-20 mm Hg (mean 6) and the coarctation diameter increased to 7-20 mm (mean 12). One patient developed a fusiform aneurysm of the aorta at the coarctation site immediately after the procedure. At reinvestigation 6-16 months (mean 12 5) after dilatation 14 of the 15 patients were normotensive. In 13 patients the residual coarctation gradient was 0-10 mm Hg (mean 3). Two patients had recoarctation with residual gradients of 20 and 24 mm Hg and underwent successful repeat dilatation. One patient had developed a small discrete aneurysm at the coarctation site.Balloon angioplasty is thus a safe and effective method of relieving unoperated aortic coarctation. The frequency of aortic aneurysm and recoarctation is small and probably related to balloon size. This early experience is encouraging , but long term results and further experience are required before this approach is used to treat coarctation generally.Surgical treatment has greatly improved the long term prognosis in patients with coarctation of the aorta. However, while operation may repair the aorta, long term follow up studies indicate that it does not cure the patient.'Relief of coarctation by balloon angioplasty is now feasible24 and, in view of the higher operative morbidity and mortality associated with reoperation, has been proposed as the first line treatment of postoperative restenosis of coarctation.5 Vascular complications and the transient benefit from angioplasty have limited the use of this technique in infancy.6Balloon angioplasty achieves its effect by disrupting the intima and media at the site of the coarctation.78 Concern over the possibility of late aneurysm formation at the site of dilatation9 10 has also restricted the adoption of the technique for relief of unoperated coarctation after infancy.Requests for reprints to Dr Christopher Wren, Ward 23, Freeman Hospital, Newcastle upon Tyne NE7 7DN.Accepted for publication 6 July 1987 This report presents the immediate results of balloon angioplasty in a consecutive group of patients over 12 months of age and the results of reinvestigation one year later. Patients and methods PATIENTS

It is important to identify preoperatively coronary arteries that may interfere with right ventricular outflow tract reconstruction. An aortogram with steep caudal and left oblique angulation is useful in identifying anomalous coronary arteries and more importantly it defines the relation of these vessels to the right ventricular outflow tract.