A patent arterial duct in pre-term neonates is frequent. Systemic complications consecutive to left-to-right shunting are well known but fatal myocardial ischaemia has not been described till now. The presented premature baby died from catecholamine refractory cardiogenic shock. Autoptic examination revealed acute ischaemic changes predominantly in the inner third of myocardium, speaking of coronary hypoperfusion due to a steal phenomenon secondary to the patent arterial duc

Fluri, Simon

Pavlovic, Mladen

Wagner, Bendicht P.

RERO DOC Digital Library

Cardiology in the Young (2010), 20: 108–110doi:10.1017/S1047951109991028r Cambridge University Press, 2010Brief ReportPatent arterial duct, bottle-meal, and fatal myocardialischaemia*Simon Fluri,1 Mladen Pavlovic,2 Bendicht P. Wagner11Department of Pediatrics, Pediatric Intensive Care Unit, University Hospital; 2Pediatric Cardiology, Inselspital,Bern, SwitzerlandAbstract A patent arterial duct in pre-term neonates is frequent. Systemic complications consecutive to left-to-right shunting are well known but fatal myocardial ischaemia has not been described till now. Thepresented premature baby died from catecholamine refractory cardiogenic shock. Autoptic examinationrevealed acute ischaemic changes predominantly in the inner third of myocardium, speaking of coronaryhypoperfusion due to a steal phenomenon secondary to the patent arterial duct.Keywords: Premature newborn; steal phenomenon; myocardial infarction; oral-feeding route; preventionReceived: 4 May 2009; Accepted: 22 November 2009; First published online 1 March 2010APATENT ARTERIAL DUCT IS A FREQUENT FINDINGin premature infants. Substantial left-to-rightshunting through the ductus is associatedwith several systemic complications: the risk ofintraventricular haemorrhage, necrotising entero-colitis, decreased renal function, bronchopulmonarydysplasia, and death may be increased.1 However,fatal myocardial ischaemia does not appear as aknown complication of the patent arterial duct.Case reportThis 1110-gram twin boy was delivered by cesareansection at 27 1/7 weeks of gestation. Apgar scoreswere 1, 3, and 5 at 1, 5, and 10 minutes,respectively. He was intubated in the delivery roomand a surfactant was administered twice. The chestX-ray showed grade IV hyaline membrane disease.On day 5 of life the boy was extubated and puton nasal continuous positive airway pressure therapyfor another 23 days. Apnea of pre-maturity wassuccessfully treated with caffeine citrate; no additionaloxygen was needed. At 1 month of life, cardiacauscultation showed a 4/6 systolic murmur. A patentarterial duct of 2–3millimetres diameter with arelevant left-to-right shunt was confirmed in echo-cardiography. No signs of cardiovascular decompensa-tion was found: renal function with creatinine at 48micrograms per litre and digestion were normal;respiration was stable, that is respiration rate at 60 perminute and 95% oxygen saturation, chest X-rayshowed mild cardiomegaly and hypercirculation;systolic/diastolic/mean blood pressure was 50/28/36millimetres of mercury, heart rate at 150 per minute.Cerebral sonography showed an elevated resistanceindex (0.98) with decreased intracerebral diastolicflow velocity.2 No attempt to close patent arterialduct was initiated.In the sixth week of life, at the gestational age of32 6/7 weeks, the boy was offered to drink fromthe bottle. He is on an eight-meal regimen with30 millilitres of human milk per meal, that is 150millilitres per kilogram per day. After 45 minutes ofthe bottle, he started abruptly with tachypnea,retractions, flaring of the nasal alae, grunting, andoxygen requirement of up to a 30%. Oscillome-trically measured blood pressure was 40/22/26millimetres of mercury. Respiratory distress wasfollowed by bradypnea and clinical signs of shock.*This case report obtained the approval for publication from the InstitutionalReview Board.Correspondence to: Dr Simon Fluri, MD, Department of Pediatrics, PediatricIntensive Care Unit, Inselspital, CH-3010 Bern. Tel: 141 316 322 111; Fax:141 316 320 784; E-mail: simon.fluri@insel.chhttps:/www.cambridge.org/core/terms. https://doi.org/10.1017/S1047951109991028Downloaded from https:/www.cambridge.org/core. University of Basel Library, on 30 May 2017 at 13:04:53, subject to the Cambridge Core terms of use, available atMainly metabolic acidosis (pH 6.7, CO2 58 milli-metres of mercury, base excess 26.9 millimols per litre,bicarbonate 7.2 millimols per litre) and arterialhypotension (34/28/30 millimetres of mercury) werefound. He was intubated with ketamine and pancur-onium and ventilated with a 90% oxygen requirementand a peak inspiratory pressure going up to amaximum of 26 centimetres in the water column toobtain tidal volumes of 7.5 millilitres per kilogram.Echocardiography was performed showing an impor-tant impairment of left ventricular function with anejection fraction of 19%.Blood pressure was 35/28/30 millimetres ofmercury. Arterial and central venous catheters wereplaced and first dobutamine and second epinephrinewere administered to maintain blood pressure in alow normal range, that is, 34/24/29 millimetres ofmercury. In the absence of dehydration and the highsuspicion of cardiogenic shock, no fluids were given.Troponin I was 46.9 micrograms per litre. Noelectrocardiography was performed. One hour beforedeath, severe bradycardia and hypotension (24/12/18 millimetres of mercury) finally required heartmassage and epinephrine boli. The boy died 6 hoursafter the onset of respiratory distress from irrever-sible, catecholamine refractory cardiogenic shock.The autopsy showed a patent arterial duct. Thecoronary arteries were inconspicuous. The microscopicexamination of the heart revealed acute ischaemicchanges of the inner third of the myocardium,including subendocardial bands of necrosis (Fig 1a)as well as multiple foci of wavy myocardial fibres(Fig 1b) in both ventricles. No myocarditis waspresent. No signs of pulmonary aspiration were foundmicroscopically.DiscussionFatal myocardial ischaemia in the newborn isextremely rare.3 Most often it is seen in associationwith congenital cardiac disease, specifically, obstruc-tive lesions, that is, aortic stenosis, anomalousorigin of left coronary artery, and tricuspidalabnormalities. Another cause of neonatal myocardialinfarction is embolic injuries of coronary arteries.Coronary thrombosis with focal intimal thickeningand coronary spasm in stressed newborns isreported. Impaired coronary perfusion because ofincreased work demands created by unusually briskpulmonary vasoconstriction in newborn with pul-monary hypoxia is described4. In contrast, ductalsteal phenomenon secondary to patent arterial ducthas not been described so far as a cause of fatalmyocardial ischaemia.A recent transthoracic Doppler echocardiographystudy showed decreased left anterior descendingcoronary artery blood flow as a result of patentarterial duct; coronary perfusion improved after coilclosure of arterial duct.5 In another study, STdepressions on electrocardiogram suggesting ischae-mia were found in a group of neonates with patentarterial duct and respiratory distress syndrome; STdepressions disappeared after surgical ligation of thearterial duct.6In our case, there was no pulmonary impairment,metabolic disturbance, or infectious disease. Respira-tory distress syndrome was the first sign of cardiacdecompensation without any sign of bronchopulmon-ary aspiration. Blood pressure could be maintainedwithin low normal ranges with the exception of thelast 2 hours of life. The fact that acute ischaemicchanges were predominantly found in the inner layerof the myocardium supports the diagnosis ofmyocardial ischaemia as the result of the ductal stealphenomenon secondary to a patent arterial duct,because the inner third of the myocardium is typicallyperfused during diastole. The ductal steal pheno-menon results in a reduced diastolic blood pressureand therefore compromises coronary artery perfusion,comparable to the well-known and routinely measuredFigure 1.Postmortem histopathologic examination of the heart yielding acuteischaemic changes; haematoxylin and eosin-stained tissue sections.(a) Subendocardial band of myocyte necrosis (asterisks) withhypereosinophilia and pycnotic nuclei and (b) wavy myocard fibres.Vol. 20, No. 1 Fluri et al: Patent arterial duct and myocardial ischaemia 109https:/www.cambridge.org/core/terms. https://doi.org/10.1017/S1047951109991028Downloaded from https:/www.cambridge.org/core. University of Basel Library, on 30 May 2017 at 13:04:53, subject to the Cambridge Core terms of use, available atreduced diastolic middle cerebral artery blood flowvelocity secondary to patent arterial duct.7Bottle feeding represents an important physical effortin every neonate. Very low birthweight newbornscannot increase their resting metabolism by more than15% for physical activity.8 Bottle feeding significantlyincreases respiratory rate and can decrease oxygensaturation.9 This physical activity increases cardiacoutput and therefore myocardial oxygen consumption.With regard to these facts, the oral feeding route mayhave been the trigger of this abrupt decompensation.ConclusionNewborns with a patent arterial duct and extremelylow diastolic blood pressure may be at increased risk formyocardial infarction secondary to a coronary stealphenomenon even in the absence of other organmanifestations. A cautious and slow enteral feedingregimen with extended feeding by gastric tubes may beof benefit, comparable to other neonates with acardiovascular compromise. Early diagnosis and inter-ventions to increase diastolic pressure and thereforecoronary artery perfusion will contribute to improve thesurvival of premature children with patent arterial duct.References1. Van Overmeire B, Smets K, Lecoutere D, et al. A comparison ofibuprofen and indomethacin for closure of patent ductusarteriosus. N Engl J Med 2000; 343: 674–681.2. Couture A, Veyrac C, Baud C, Saguintaah M, Ferran JL.Advanced cranial ultrasound: transfontanellar Doppler imagingin neonates. Eur Radiol 2001; 12: 2399–2410.3. Kilbride H, Way GL, Merenstein GB, Winfield JM. Myocardialinfarction in the neonate with normal heart and coronary arteries.Am J Dis Child 1980; 134: 759–762.4. Rowe RD, Hoffmann T. Transient myocardial ischemia of thenewborn infant: a form of severe cardiorespiratory distress in full-term infants. J Pediatr 1972; 81: 243.5. Harada K, Toyono M, Tamura M. Effects of coil closure of patentductus arteriosus on left anterior descending coronary artery bloodflow using transthoracic Doppler echocardiography. J Am SocEchocardiogr 2004; 17: 659–663.6. Way GL, Pierce JR, Wolfe RR, McGrath R, Wiggins J,Merenstein GB. ST depression suggesting ischemia in neonateswith respiratory distress syndrome and patent ductus arteriosus.J Pediatr 1979; 95: 609–610.7. Weir FJ, Ohlsson A, Myhr TL, Fong K, Ryan ML. A patentductus arteriosus is associated with reduced middle cerebralartery blood flow velocity. Eur J Pediatr 1999; 158: 484–487.8. Polin, Fox. Fetal and Neonatal Physiology, 2nd edition. WBSaunders Company, Philadelphia, USA, 1998.9. Blaymore Bier JA, Ferguson AE, Morales Y, Liebling JA, Oh W,Vohr BR. Breastfeeding infants who were extremely low birthweight. Pediatrics 1997; 100: E3.110 Cardiology in the Young February 2010https:/www.cambridge.org/core/terms. https://doi.org/10.1017/S1047951109991028Downloaded from https:/www.cambridge.org/core. University of Basel Library, on 30 May 2017 at 13:04:53, subject to the Cambridge Core terms of use, available at

Patent arterial duct, bottle-meal, and fatal myocardial ischaemia

Abstract

Similar works

Full text

Available Versions

RERO DOC Digital Library