HISTORY, CURRENT ILLNESS AND PHYSICAL EXAMINATION

PERSONAL HISTORY
52-year-old male, ex-smoker of 10 cigarettes a day for the last 5 years, with no personal or family history of interest. He does not take any treatment.

CURRENT ILLNESS
He presented at home with oppressive chest pain, continuous, with associated vegetative crusade. After about 10 hours with these symptoms, he suffered syncope, for which he finally consulted an external centre. An electrocardiogram showed complete atrioventricular block (AVB) with ST-segment elevation predominantly in DII-DIII and aVF. The infarction code was activated and immediate fibrinolysis was performed, starting antiplatelet therapy with acetylsalicylic acid (ASA) and clopidogrel, according to local protocol. Subsequently, he was transferred urgently to our hospital, where persistent chest pain and ST-segment elevation were observed 90 minutes after fibrinolysis. Rescue angioplasty was performed, revealing generalised vasoconstriction of the left tree, with atheromatosis but without significant stenosis and a subtotal lesion in the middle third of the right coronary artery (RCA). After passing the guidewire through the culprit lesion, an image compatible with coronary dissection was observed, which was resolved by implanting three drug-eluting stents in the origin, middle and distal third of the right coronary artery (RCA), with acceptable angiographic results and good clinical response. After 72 hours in the intensive care unit (ICU), he was transferred to the hospital ward.

PHYSICAL EXAMINATION
General appearance was fair. Skin pallor. Dyspnoea on speech. SpO2 97% with oxygen therapy in nasal goggles at 2 l/min. Jugular ingurgitation present at 45o. Blood pressure 105/79 mmHg.
Good capillary refill. Cardiac auscultation: rhythmic tones at 95 bpm, no audible murmurs.
Hypoventilation at both bases, no added sounds. Lower limbs without oedema or impaction. Peripheral pulses present.

COMPLEMENTARY TESTS
Admission CBC: leukocytes 19630/mm3 with 79% neutrophils. Hb 14 g/dl. Platelets 293000. No alterations in the coagulation study. Glucose 183 mg/dl. Creatinine 1.1 mg/dl. Urea 44 mg/dl. Na+ 139 mEq/l. K 4.1 mEq/l. GGT 122 U/I. AST 339 U/I. Bilirubin 0.8 mg/dl. CK 3472 UI. cTnT-hs 3779 ng/l (normal values 0-14). Total cholesterol 155 mg/dl. Triglycerides 145 mg/dl.
Urgent echocardiography on the ward: non-dilated left ventricle (LV) with akinesia of the entire inferior wall and compensatory hyperkinesia of the anterior and lateral wall.
Overall, there is mild LV dysfunction, with an estimated ejection fraction of 48%. Significant dilatation of the right chambers with very severe right ventricular (RV) systolic dysfunction (TAPSE 2 mm and S ́ tricuspid annulus 2.5 cm/s) and suggestive of increased central venous pressure. Acute tricuspid insufficiency with triangular morphology of its Doppler spectrum as a sign of severity and mild mitral insufficiency. Absence of pericardial effusion.
Electrocardiogram (ECG) on the ward: sinus rhythm at 92 bpm, PR 134 ms. QRS 112 ms, lower QS with persistent ST elevated 1 mm in these leads and in V3-V4 with high voltage R in V2. QTc 442 ms.
Coronary angiography (second procedure):
Left coronary artery: after intracoronary injection of nitroglycerin, atheromatous arteries are observed, although without angiographically significant lesions.
Right coronary artery: ostial occlusion. Some heterocoronary collaterals are observed retrogradely filling the more distal branches. Repermeabilisation was attempted with poor results, only a slight anterograde flow with a distal image of thrombus and residual dissection.

CLINICAL EVOLUTION
During his stay on the hospital ward, the patient presented unfavourable clinical data, with the development of symptoms and signs of acute right heart failure (HF). We performed an urgent echocardiography, which revealed very severe dilatation and dysfunction of the RV.
Taking into account this evolution and knowing that the epicardial coronary flow, which was achieved in the first coronary angiography was TIMI II, it was decided to perform a new coronary angiography (96 hours after the first one), which showed a total occlusion of the RCA compatible with subacute thrombosis of the stent previously implanted at the ostial level, and repermeabilisation was attempted with poor results due to the presence of thrombus and residual dissection.
After the procedure, he was admitted to the ICU, where an infusion of levosimendan was started. A few hours later, the patient presented with a marked drop in blood pressure, accompanied by a loud and intense holosystolic murmur on cardiac auscultation. A new bedside echocardiography was performed, showing a continuity solution in the interventricular septum at the lower basal level and a left-right shunt with a maximum gradient of 40 mmHg, compatible with a ventricular septal defect (VSD) as an acute mechanical complication of acute myocardial infarction (AMI).
In view of this situation, he was transferred to the transplant centre of reference to assess the implantation of an extracorporeal membrane oxygenator (ECMO). 12 hours after transfer, peripheral veno-arterial (V-A) femoral-femoral ECMO was implanted as a bridge to decision, maintaining continuous perfusion of dobutamine at 10 mcg/kg/min and noradrenaline at 0.5 mcg/kg/min.
The patient required mechanical ventilation due to respiratory failure. At a multidisciplinary meeting, given the impossibility of surgically treating the defect and the poor haemodynamic evolution, it was decided to include the patient in emergency 0 for cardiac transplantation.
After 7 days of circulatory support with ECMO, an orthotopic heart transplant from a brain-dead donor was performed. Extracorporeal circulation was discontinued with peripheral V-A femoro-axillary ECMO due to haemodynamic lability and preoperative hypoxaemia. ECMO was withdrawn on the fourth day after transplantation, with good evolution. The patient was discharged after 67 days of hospitalisation.

DIAGNOSIS
Inferior and right ventricular AMI.
Ineffective fibrinolysis. Thrombotic occlusion of the RCA. Percutaneous transluminal coronary angioplasty (PTCA) complicated by coronary dissection. Implantation of three drug-eluting stents in RCA. Subacute thrombosis of the stents implanted in the RCA. Unsuccessful PTCA.
Acute HF and cardiogenic shock secondary to RV failure.
Ruptured interventricular septum.
ECMO as mechanical circulatory support bridging to transplantation.
Orthotopic heart transplantation.
