HypertroponinaeHypertroponinaemiamia

Michael Michael StewartStewart

CT1 ACCSCT1 ACCS

Case 1Case 1

64 year old male64 year old male Known history of IHD – 2x NSTEMI, Known history of IHD – 2x NSTEMI,

UAUA Two hours of central chest pain, Two hours of central chest pain,

identical to previous MIidentical to previous MI ECG: Lateral ST depressionECG: Lateral ST depression Trop T 0.07Trop T 0.07

Case 2Case 2

72 year old male72 year old male Presents with three hours central Presents with three hours central

chest pain, onset during dancingchest pain, onset during dancing Nausea, mildly dyspnoeicNausea, mildly dyspnoeic Ex-smoker; hypertensiveEx-smoker; hypertensive Not diabetic, no FH of IHDNot diabetic, no FH of IHD

Case 2Case 2

ECG shows dynamic inferior ST ECG shows dynamic inferior ST depressiondepression

Pain eased after IV GTN and Pain eased after IV GTN and morphine with resolution of ECG morphine with resolution of ECG changeschanges

Troponin 0.56Troponin 0.56

Case 3Case 3

62 year old female62 year old female Onset of palpitations and dyspnoea Onset of palpitations and dyspnoea

on wakingon waking GP found irregular pulse, rate ~160GP found irregular pulse, rate ~160

Case 3Case 3

Hypertensive; no other significant Hypertensive; no other significant co-morbidityco-morbidity

ECG: Fast AF, rate ~170ECG: Fast AF, rate ~170 BP 100/60BP 100/60 Pale, clammy, drowsyPale, clammy, drowsy DC Cardioversion – SR restoredDC Cardioversion – SR restored Troponin 0.13Troponin 0.13

TroponinTroponin

Component of cardiac and striated muscleComponent of cardiac and striated muscle Calcium binding initiates conformational Calcium binding initiates conformational

change to permit myosin to bind to actin change to permit myosin to bind to actin filamentfilament

Myosin conformational cycling on actin Myosin conformational cycling on actin acts as ‘molecular motor’ for muscle acts as ‘molecular motor’ for muscle contractioncontraction

Cardiac Troponins are specific for cardiac Cardiac Troponins are specific for cardiac myocyte damagemyocyte damage

Troponin is NOT specific for myocardial Troponin is NOT specific for myocardial infarctioninfarction

PICI/SICI/NICIPICI/SICI/NICI

Primary Ischaemic Cardiac InjuryPrimary Ischaemic Cardiac Injury

Secondary Ischaemic Cardiac InjurySecondary Ischaemic Cardiac Injury

Non-Ischaemic Cardiac InjuryNon-Ischaemic Cardiac Injury

PICIPICI

Coronary artery occlusion/stenosis Coronary artery occlusion/stenosis by thrombotic diseaseby thrombotic disease

STEMI/NSTEMISTEMI/NSTEMI

NSTEMINSTEMI

Any two of:Any two of: Typical chest painTypical chest pain Typical ECG changesTypical ECG changes Rise in cardiac enzymesRise in cardiac enzymes

New definition!New definition!

2007 Universal Definition2007 Universal Definition

Troponin > 99Troponin > 99thth centile of reference centile of reference rangerange (Locally agreed at Trop T > 0.1)(Locally agreed at Trop T > 0.1)

PLUS:PLUS: Ischaemic symptomsIschaemic symptoms ECG changesECG changes Regional wall motion abnormalityRegional wall motion abnormality Loss of viable myocardium on imagingLoss of viable myocardium on imaging

SICISICI

Secondary cause of coronary artery Secondary cause of coronary artery obstructionobstruction Embolic disease; during PCI; during Embolic disease; during PCI; during

CABGCABG Coronary vasospasm or inflammationCoronary vasospasm or inflammation

Primary; vasculitides; SLEPrimary; vasculitides; SLE Increased myocardial oxygen demandIncreased myocardial oxygen demand

Tachyarrythmias; prolonged exercise; Tachyarrythmias; prolonged exercise; sympathomimetic drugs; heart failure; PEsympathomimetic drugs; heart failure; PE

NICINICI

Direct traumaDirect trauma Penetrating; blunt; surgicalPenetrating; blunt; surgical

MyocarditisMyocarditis Infectious; auto-immune; drug/alcohol; Infectious; auto-immune; drug/alcohol;

inflammatoryinflammatory MetabolicMetabolic

Renal failure; multiple organ failure; Renal failure; multiple organ failure; sepsissepsis

CasesCases

Case 1: Typical chest pain, Trop T Case 1: Typical chest pain, Trop T 0.070.07 PICI, not criteria for NSTEMIPICI, not criteria for NSTEMI

Case 2: Typical chest pain, Trop T Case 2: Typical chest pain, Trop T 0.560.56 NSTEMINSTEMI

Case 3: Fast AF, no pain, Trop T 0.13Case 3: Fast AF, no pain, Trop T 0.13 SICI ( + NICI )SICI ( + NICI )

Questions?Questions?

SummarySummary

Troponins are a sensitive marker of Troponins are a sensitive marker of cardiac myocyte damagecardiac myocyte damage

Not all cardiac myocyte damage Not all cardiac myocyte damage represents acute myocardial represents acute myocardial infarctioninfarction

Primary, secondary, and non-Primary, secondary, and non-ischaemic causes existischaemic causes exist

ReferencesReferences Thygesen, Kristian, Alpert, Joseph S., White, Harvey D., on behalf Thygesen, Kristian, Alpert, Joseph S., White, Harvey D., on behalf

of the Joint ESC/ACCF/AHA/WHF Task Force for the Redefinition of the Joint ESC/ACCF/AHA/WHF Task Force for the Redefinition of Myocardial Infarction, of Myocardial Infarction, Universal Definition of Myocardial InfarctionUniversal Definition of Myocardial InfarctionJ Am Coll Cardiol 2007 50: 2173-2195J Am Coll Cardiol 2007 50: 2173-2195

Collinson, P O, Stubbs, P JCollinson, P O, Stubbs, P J

Are troponins confusing?Are troponins confusing?Heart 2003 89: 1285-1287Heart 2003 89: 1285-1287

http://www.trauma.org http://www.trauma.org