2005 OPEN FORUM Abstracts
Acute Myocardial Infarction complicated by Ventricular Septum Rupture and Cardiogenic Shock in a 4 year old
Richard Piekutowski RRT-NPS, Jason Weber RRT, Michael D. Dettorre D.O., Margaret J Wojnar MD. The Pennsylvania State University's Milton S. Hershey Medical Center, The Penn State Children's Hospital, Hershey, Pa.
Introduction: Mechanical complications of Acute Myocardial Infarction (AMI) are associated with high mortality rates. Free wall rupture and ventricular septum rupture are extremely well documented in the adult population but documentation is almost non-existent in the pediatric patient. Patients who do not receive timely resuscitation and surgical treatment have a high mortality rate. It is estimated that before the introduction of thrombolysis therapy that 1-2% of all AMI patients had acute ventricular rupture as a complication. Now the incidence has declined to 0.2%. This is clearly demonstrated in the GUSTO-1 trials. While it is established that acute ventricular septum rupture is rare in adults it is even more elusive in children.
Case Study: A 4 year old, 20kg female who apparently woke up in the morning and stated that she did not feel well and collapsed. The family initiated CPR. She was resuscitated at the outlying facility and transferred to our PICU for further management. She had no significant past medical history. She was not taking any medications. She had no viral or bacterial infections in the recent past. Paternal history was that the father is positive for IgA Nephropathy. There was no significant history on the patient's maternal side. Upon admission the patient's Troponin was 203.64. She was re-intubated with a 5.0 uncuffed endotracheal tube and placed on a Siemens Servo 300 ventilator SIMV, VT 240mL, f 16, PEEP 5, PSV 5, FIo2 1.0. ABG, pH 7.40, PACO2 31, PAO2 299, HCO319, BE -4. Initial Echo cardiogram findings revealed a large VSD present possibly due to an ischemic rupture of the ventricular septum or a large septal aneurysm rupture. The patient remained hemodynamically unstable and had 2 episodes of hypotension and bradycardia which needed aggressive resuscitation and CPR, 24 hours into admission she was placed on V-A ECMO in order to decrease the cardiac workload and for hemodynamic stabilization. Initial ECMO settings were 1000ml flow, 650ml sweep, FIo2 .50. ACT's were maintained at 180-220 seconds. The ECMO circuit we utilized was a 3/4 inch tubing with a Tygon raceway, A 30cc bladder with a Seabrook controller, a Medtronic 1500 silicone oxygenator, 2 DLP 6400 pressure monitors to monitor pre and post oxygenator pressures, a CDI 500 blood gas analyzer and a Seabrook ECMO Temperature controller. A Respiratory Therapist (RRT) and Nurse (RN) team cared for the patient at all times. ECHO cardiograms were done daily and showed increased contractility. On day eight the ECMO flow was weaned in order to increase the workload of the heart and obtain better visualization of the VSD and LV function. An ECHO " stress study" revealed that there were three VSD's and free wall thinning of the posterior left ventricle. After about thirty minutes the patient became tachycardic and hemodynamically unstable. The ECMO flow was increased. On day ten the patient was taken to the cath lab. Catherization revealed a recent MI, post MI apical muscular VSD's, akinetic interventricular septum, small L to R VSD shunt, elevated wedge/PA pressures, and an occluded LAD. There was no collateral circulation to the LAD. The RCA and circumflex branches were normal. Our medical team decided that the patient should be evaluated at another facility for possible cardiac transplant. The highly specialized ECMO transport team from the Wilford Hall United States Air Force Medical Center transported the patient to another Pennsylvania facility without complications.
Significance of the Case: This case represents an unusual medical condition in a very young patient. The multidisciplinary, multifacility team approach worked well in the care of this patient. The patient was resuscitated, repaired, weaned from ECMO and received a heart transplant.