โรงพยาบาลสรรพสิทธิประสงค์ อุบลราชธานี How to manage ACS Complications นพ.วีระ มหาวนากูล กลุม่ งานอายุรกรรม โรงพยาบาลสรรพสิทธิประสงค์อบุ ลราชธานี Complications of Acute Coronary Syndrome • • • • • • • • • Arrhythmic complications of ACS Mechanical complications of ACS Pump failure Right ventricular infarction Left ventricular aneurysm Left ventricular pseudoaneurysm Pericardial complications Complications involving bleeding Complications of percutaneous coronary intervention Complications of Myocardial Infarction • arrhythmic • mechanical • inflammatory (early pericarditis and post-MI syndrome) • right ventricular (RV) infarction and cardiogenic shock • left ventricular mural thrombus (LVMT) Arrhythmic Complications • 90% of patients cardiac arrhythmia immediate or during MI • 25% of patients first 24 hr • The incidence of arrhythmia: STEMI > NSTEMI • Most peri-infarct arrhythmias are benign selflimited • Hypotension myocardial oxygen requirements malignant ventricular arrhythmias (aggressively monitored and treated) Arrhythmic Complications Pathophysiology • autonomic dysfunction enhanced automaticity of the myocardium and conduction system • Electrolyte imbalances (hypoK and hypoMg) and hypoxia cardiac arrhythmia • damaged myocardium = substrate reentrant circuits (tissue refractoriness) Peri-infarction arrhythmias • • • • • • • Supraventricular tachyarrhythmias Accelerated junctional rhythms Bradyarrhythmias Atrioventricular (AV) blocks Intraventricular blocks Ventricular arrhythmias Reperfusion arrhythmias Supraventricular tachyarrhythmias Sinus Tachycardia • enhanced sympathetic activity transient hypertension or hypotension Causes: • Pain • Anxiety • Heart failure • Hypovolemia • Hypoxia • Anemia • Pericarditis • Pulmonary embolism Supraventricular tachyarrhythmias Sinus Tachycardia Treatment strategies: • adequate pain medication, • diuresis heart failure • Oxygenation • volume repletion hypovolemia • anti-inflammatory agents pericarditis • Beta-blockers and/or nitroglycerin relieve ischemia Supraventricular tachyarrhythmias • Premature atrial contractions (PAC’s) • PAC’s paroxysmal SVT, atrial flutter, or atrial fibrillation • ↑left ventricular (LV) diastolic pressure or pericarditis (inflammation) atrial distention • No specific therapy: ?? occult heart failure ?? Supraventricular tachyarrhythmias • • • • Paroxysmal supraventricular tachycardia (PSVT) Incidence in AMI < 10% No Hypotension Adenosine (No data) No significant LV failure IV diltiazem or beta-blocker severe heart failure or hypotension synchronized electrical cardioversion Supraventricular Tachycardia Supraventricular Tachycardia Supraventricular tachyarrhythmias • • • • Atrial flutter < 5% of AMI. Transient Sympathetic overstimulation of the atria Treatment strategies: atrial fibrillation ventricular-rate control with drugs is less easily • synchronized electrical cardioversion: with 50 J, or the biphasic equivalent relatively promptly decrease coronary blood flow and/or hemodynamic compromise • refractory to medication overdrive atrial pacing Atrial Flutter Atrial Flutter Atrial Flutter Supraventricular tachyarrhythmias • Atrial fibrillation • 10-15% in AMI • Onset < 1 hour caused by LV failure, ischemic injury to the atria, or RV infarction • Pericarditis & conditions ↑left atrial pressure atrial fibrillation • ↑mortality and stroke: Anterior wall MI. Atrial fibrillation Atrial fibrillation Supraventricular tachyarrhythmias Atrial fibrillation unstable condition • worsening ischemic pain and/or hypotension electrical cardioversion • Synchronized electrical cardioversion 200 J or the biphasic equivalent • Conscious sedation (preferred) or general anesthesia is advisable Supraventricular tachyarrhythmias Atrial fibrillation stable condition • immediate objective controlling the ventricular response • Not respond to cardioversion IV amiodarone or IV digoxin (in patients with LV dysfunction or heart failure) achieve rate control. • IV beta-blocker & IV diltiazem alternative for slowing the ventricular rate, with caution in moderate-to-severe heart failure Supraventricular tachyarrhythmias Atrial fibrillation • AF & atrial flutter ↑risk of thromboembolism • Anticoagulation: unfractionated heparin or low molecular weight heparin (LMWH) (If no contraindications) • Transient AF ??? Anticoagulation Accelerated Junctional Rhythm • ↑ automaticity of the junctional tissue heart rate of 70-130 /min. • most common in inferior MI • Treatment correcting the underlying ischemia Accelerated Junctional Rhythm Arrhythmic Complications Bradyarrhythmias • Sinus bradycardia • Junctional bradycardia Arrhythmic Complications Bradyarrhythmias • • • • Sinus bradycardia common in acute inferior or posterior MI first 1-2 hours after AMI Mechanism: stimulation of cardiac vagal afferent receptors efferent cholinergic stimulation of the heart (↓ myocardial oxygen demand) bradycardia and hypotension ventricular arrhythmias (treated aggressively) Arrhythmic Complications sinus bradycardia • No adverse signs or symptoms therapy is typically unnecessary • HR < 40 bpm with hypotension atropine sulfate 0.5-1 mg IV every 3-5 min. (maximum of 0.03-0.04 mg/kg) • inability to reverse hypotension with atropine in inferior MI volume depletion and/or RV infarction Arrhythmic Complications sinus bradycardia • atropine is ineffective transcutaneous or transvenous pacing • Transplanted hearts do not respond to atropine require cardiac pacing • Additional pharmacologic intervention dopamine 5-20 mcg/kg/min IV, epinephrine 210 mcg/min, and/or dobutamine. Arrhythmic Complications Junctional bradycardia • Junctional bradycardia a protective AV junctional escape rhythm, rate of 35-60 bpm in inferior MI • Usually not associated with hemodynamic compromise • Treatment:not required Arrhythmic Complications AV and Intraventricular Blocks • SA node ปกติรับเลือดจาก right coronary artery (RCA) ประมาณ 60% และรับจาก left circumflex artery (LCX) ประมาณ 40% • AV node ปกติรับเลือดจาก RCA ประมาณ 90% และรับจาก LCX ประมาณ 10% • His bundle ส่วนใหญ่ได้ รับเลือดจาก RCA และส่วนน้ อยจาก septal perforators จาก left anterior descending artery (LAD) Arrhythmic Complications AV and Intraventricular Blocks • Main bundle branch และ Right bundle branch รับเลือดจาก septal perforators จาก LAD ส่วนน้ อยได้ รับ collateral circulation จาก LCX และ RCA • Posterior fascicle ได้ รับ dual blood supply จาก AV nodal artery และ septal perforators จาก LAD • Anterior fascicle ส่วนใหญ่ได้ รับเลือดจาก septal perforators และส่วนน้ อยจาก AV nodal artery Arrhythmic Complications AV and Intraventricular Blocks • First-degree AV block • 15% of AMI, most common inferior wall MI • conduction disturbances above the His bundle CHB or asystole is rare • CCB & ß-blockers cause or exacerbate 1˚AV block stopped if hemodynamic impairment /higher-degree block • No specific therapy, atropine if BP ↓ • cardiac monitoring: possible higher block. Arrhythmic Complications AV and Intraventricular Blocks • Second-degree AV block • Mobitz type I (Wenckebach) AV block 10% of AMI (most common inferior MI), 90% of 2˚ AV block in AMI • Not affect overall prognosis • Not require treatment. If HR is inadequate for perfusion atropine 0.5-1 mg IV • Transcutaneous/temporary transvenous pacing Rare AV Block 1st AV block 2nd AV block Mobitz I (Wenckebach) Arrhythmic Complications AV and Intraventricular Blocks • Mobitz type II AV block accounts: < 1% in AMI (10% of all second-degree AV blocks) • associated with anterior infarction • poor prognosis (ถ้ าร่วมกับมี complete heart block mortality rate ประมาณ 80%) • immediately transcutaneous pacing/atropine • Atropine helps in 50% of cases, but occasionally worsens the block Mobitz I & II AV Block Arrhythmic Complications AV and Intraventricular Blocks • Third-degree AV block • 5-15% in AMI (anterior or inferior MI) • inferior MI: gradually progress from 1˚AV block / Mobitz I AV block • most patients supranodal or intranodal escape rhythm stable, narrow QRS & rates > 40 bpm • 30% below the His bundle escape rhythm < 40 bpm & wide QRS complex Third degree heart block Arrhythmic Complications AV and Intraventricular Blocks • CHB in inferior MI usually responds to atropine • resolves within a few days without the need for a temporary or permanent pacemaker • Mortality rate for inferior MI + CHB 15% (Higher in RV infarction) • Atropine may not help & worsen the block Temporary transcutaneous / transvenous pacing Complete Heart Block Arrhythmic Complications AV and Intraventricular Blocks • persistent symptomatic bradycardia /unresolved with lysis or percutaneous coronary intervention Permanent pacing • anterior MI: intraventricular block / Mobitz type II AV block third-degree AV block high mortality rate • Immediate treatment: atropine and/or transcutaneous / temporary transvenous pacing • If survive often permanent pacemaker Arrhythmic Complications AV and Intraventricular Blocks • Intraventricular blocks • 1 or more fascicular block 15% of AMI • Isolated left anterior fascicular block (LAFB) 3-5% of AMI (complete AV block uncommon) • Isolated left posterior fascicular block (LPFB) 1-2% of AMI (blood supply of the posterior fascicle is larger than that of the anterior fascicle relatively large infarct and high mortality rate) Arrhythmic Complications AV and Intraventricular Blocks • The right bundle branch: dominant blood supply from the left anterior descending (LAD) artery. • new RBBB 2% of AMI, suggests a large infarct territory cardiogenic shock & Death • RBBB with LAFB (bifascicular block) เกิดจาก occlusion of the proximal LAD coronary artery (Mortality related to the amount of muscle loss, CHB-uncommon) Arrhythmic Complications RBBB Arrhythmic Complications AV and Intraventricular Blocks • Bifascicular block + first-degree AV block trifascicular block (40% complete heart block) Trifascicular Block Arrhythmic Complications: Ventricular Arrhythmias • Acute phase arrhythmia เกิดใน 48 ชัว่ โมงแรก สาเหตุ ส่วนใหญ่จะเป็ น reversible cause เช่น ภาวะ ischemia, left ventricular wall stress ถ้ าได้ รับการแก้ ไขก็จะไม่มีผล ต่อการพยากรณ์โรคในระยะยาว • Chronic phase arrhythmia มักจะเป็ น monomorphic VT กลไกการเกิดเป็ น reentry ซึง่ เกิดจาก การที่มีแผลเป็ นในผนังกล้ ามเนื ้อหัวใจ ผู้ป่วยกลุม่ นี ้มีการพยากรณ์โรค ระยะยาวไม่ดี มีโอกาสเกิด sudden cardiac death สูงใน อนาคต Arrhythmic Complications: Ventricular Arrhythmias • Premature ventricular contractions (PVC’s) • prophylactic suppression of PVCs with antiarrhythmic drugs (lidocaine, etc) not recommended. • Prophylaxis ↑ risk of fatal bradycardia /asystole suppression of escape pacemakers (lidocaine เพื่อรักษา PVCs กลับทาให้ อตั ราตายเพิ่มสูงขึ ้นจาก bradyarrhythmia และ asystole ปั จจุบนั จึงมีที่ใช้ น้อยมาก) • attention correct electrolytic or metabolic abnormalities, identify & treat recurrent ischemia. PVC’s PVC’s Arrhythmic Complications: Ventricular Arrhythmias • Accelerated idioventricular rhythm (AIVR) • 20% of AMI • wide QRS complex /regular escape rate faster than the atrial rate, but < 100 bpm • AV dissociation is frequent • Slow, nonconducted P waves • unrelated to the fast, wide QRS rhythm • short & terminate spontaneously Arrhythmic Complications: Ventricular Arrhythmias Arrhythmic Complications: Ventricular Arrhythmias • Accelerated idioventricular rhythm • SA node or AV node sustain structural damage & depress nodal automaticity and/or • an abnormal ectopic focus in the ventricle dominant pacemaker • Do not affect prognosis • No definitive evidence untreated occurrence increases the incidence of ventricular fibrillation or death Arrhythmic Complications: Ventricular Arrhythmias • Accelerated idioventricular rhythm • พบบ่อยใน early reperfusion neither sensitive nor specific marker for reperfusion • Suppression bradycardia or asystole left untreated Arrhythmic Complications Nonsustained ventricular tachycardia • 3 or more consecutive ventricular ectopic beats , > 100 bpm and lasting < 30 sec • multiple runs of nonsustained VT sudden hemodynamic collapse • antiarrhythmic No morbidity/mortality benefit • > 48 hr after infarction in LV systolic dysfunction (LVEF < 0.40) ↑ risk for sudden cardiac death electrophysiologic testing & appropriate therapy Arrhythmic Complications Nonsustained ventricular tachycardia • Multiple episodes of nonsustained VT intensified monitoring & attention to electrolyte imbalances • Keep Serum K > 4.5 mEq/L, and Mg > 2.0 mEq/L • Ongoing ischemia aggressively be sought and corrected Arrhythmic Complications Sustained ventricular tachycardia • 3 or more consecutive ventricular ectopic beats ,rate > 100 bpm and lasting > 30 sec or causing hemodynamic compromise that requires intervention • 20% hospital mortality rate • Rapid polymorphic VT ( >150 bpm) associated with hemodynamic instability immediate unsynchronized cardioversion of 200 J (or biphasic energy equivalent) Arrhythmic Complications Sustained ventricular tachycardia • Monomorphic VT synchronized 100 J (or biphasic energy equivalent) • Antiarrhythmic therapy: amiodarone (drug of choice) or procainamide may be attempted before electrical cardioversion • Correct electrolyte abnormalities, acid-base disturbances, hypoxia, or medication • Persistent/recurrent VT overdrive pacing Arrhythmic Complications Sustained ventricular tachycardia • lidocaine 1-1.5 mg/kg bolus และให้ ทาง iv drip ต่อ 2-4 mg/min ให้ ลดขนาดยาในผู้สงู อายุ, มีภาวะ CHF หรื อ hepatic dysfunction • amiodarone 150 mg iv ใน 10 นาทีและให้ iv drip ต่อ 1 mg/min ใน 6 ชัว่ โมง ต่อไปให้ 0.5 mg/min Arrhythmic Complications ventricular fibrillation • Primary VF greatest in the first hour, 60% of episodes occur within 4 hours, and 80% occur within 12 hours • Secondary or late VF 48 hr after an MI usually associated with pump failure and cardiogenic shock, large infarct, an intraventricular conduction delay, and an anteroseptal MI (In-hospital mortality rate of 40-60%) Arrhythmic Complications ventricular fibrillation • Treatment: unsynchronized electrical countershock 200-300 J (or biphasic energy equivalent) • electromechanical dissociation (EMD) or pulseless electrical activity (PEA) extensive myocardial ischemia/necrosis or cardiac rupture • IV amiodarone/lidocaine facilitate successful electrical defibrillation & prevent recurrent/ refractory episodes, continued IV infusion for 1224 hr • early use of ß-blockers in MI ↓ ventricular fibrillation/death Arrhythmic Complications Reperfusion Arrhythmias • believed to be a marker of successful coronary reperfusion • high incidence in patients with AMI in whom coronary reperfusion is unsuccessful • neither sensitive nor specific for reperfusion treated Accelerated Idioventricular Rhythm (AIVR) • อาจจะเป็ น PVCs, AIVR, VT หรื อ VF Mechanical Complications of MI • Ventricular free wall rupture (VFWR) • ventricular septal rupture(VSR) • papillary muscle rupture with severe mitral regurgitation (MR) Ventricular free wall rupture (VFWR) • most serious complication of AMI • VFWR leads to acute hemopericardium and death from cardiac tamponade • incidence 0.8-6.2 % declined with better 24 hour systolic blood pressure control; ↑use of reperfusion therapy, beta blockers, and ACE inhibitors; and ↓use of heparin • Percutaneous transluminal coronary angioplasty (PTCA) had an incidence of free wall rupture < receiving thrombolytic therapy. Ventricular free wall rupture (VFWR) • ส่วนใหญ่ 1st week after AMI • Involve: anterior or lateral wall • Acute severe chest pain, abrupt electromechanical dissociation, asystole, hemodynamic collapse, and death • Subacute pseudoaneurysms (vary in size ,high risk to rupture) syncope, hypotension, shock, arrhythmia, prolonged & recurrent chest pain Ventricular free wall rupture (VFWR) • • • • • • • • Risk factors Age > 70 years Female no previous MI Q waves on ECG Hypertension during the initial phase of STEMI Corticosteroid/NSAID use Fibrinolytic therapy > 14 hr after STEMI onset Ventricular free wall rupture (VFWR) • Echocardiography moderate-to-large pericardial effusion with signs of impending tamponade • Most important prevention strategy: early reperfusion therapy • IABP, IV fluids, inotropic agents, emergency pericardiocentesis. • Stable emergency surgical repair • mortality rate: high & depend on preoperative hemodynamic status ventricular septal rupture(VSR) • high mortality rate • Bimodal: high incidence in the first 24 hr, another peak on days 3-5 (rarely > 2 weeks) • median time (onset of AMI to septal rupture): 1 Day in GUSTO-I, 16 hr in SHOCK-Trial • most common in large anterior MI (occlusion of the LAD artery causing extensive septal infarcts) ST-segment elevations and Q waves in inferior leads (II, III, aVF) ventricular septal rupture(VSR) • • • • • • • Risk factors Age >65 y Female Single-vessel disease Extensive MI Poor septal collateral circulation RV involvement ventricular septal rupture(VSR) • Clinical presentation • chest pain, shortness of breath, hypotension, biventricular failure & shock with (hours to days) • new, loud & harsh holosystolic murmur LLSB & palpable parasternal systolic thrill, S3 gallops (เทียบกับ acute MR soft systolic murmur at the apex, without thrill) • กรณี cardiogenic shock identify murmur ยาก ventricular septal rupture(VSR) • Echocardiography (color Flow) Tool of choice • Cardiac catheterization confirm Dx, ประเมิน degree of left-to-right shunt, ตาแหน่งของ VSR, แยก โรค VSR จากภาวะ MR , ดู coronary artery lesion ventricular septal rupture(VSR) • Key management: prompt diagnosis & an aggressive approach to hemodynamic stabilization, angiography, and surgery • Oxygen, IABP • use of vasodilators (↓ afterload & LV pressure & left-to-right shunt) • diuretics, and inotropic agents • Medical therapy temporary stabilization before surgery ventricular septal rupture(VSR) • GUSTO-I 30-day mortality rate ของผู้ป่วยที่รักษา โดย surgical repair = 47% VS medical = 94% และ 1-year mortality rate = 53% vs 97% • Current guidelines of the ACC/AHA patients with septal rupture complicating AMI urgent surgical intervention, regardless of their clinical status • Percutaneous closure of septal rupture relatively new approach acute mitral regurgitation • MR is a common complication, results from local and global LV remodeling predictor of heart failure & death • เกิด 7-10 days หลัง MI, onset may vary according to the mechanism of MR. MR จาก Papillary muscle rupture เกิดในช่วง 1-14 วัน (median 1 วัน) • Mild-to-moderate MR silent, พบจากการทา Doppler echocardiography • Severe acute MR (rupture of papillary muscles or chordae tendineae) abrupt hemodynamic deterioration with cardiogenic shock อัตราตายสูง acute mitral regurgitation • Risk factors: advanced age, female, large infarct, previous AMI, recurrent ischemia, multivessel coronary artery disease & heart failure • Posteromedial papillary muscle > anterolateral papillary muscle (PM มี single blood supply ขณะที่ AL มี dual supply) • Papillary muscle rupture flailing or prolapse of the leaflets severe MR acute mitral regurgitation • Papillary muscle dysfunction due to scarring or recurrent ischemia MR in the subacute and chronic phases, resolve spontaneously • Large posterior infarctions acute MR จาก asymmetric annular dilation and altered function and geometry ของ papillary muscle • Dx: Echocardiography with color flow Doppler imaging • CXR pulmonary edema without cardiac enlargement acute mitral regurgitation • Presentation: • mild or moderate MR asymptomatic • acute severe MR shortness of breath, fatigue, a new apical holosystolic murmur (may be early-to-mid systolic , no thrill), flash pulmonary edema & shock acute mitral regurgitation • Cardiac catheterization should be performed to determine the extent and severity of coronary artery disease • Treatment: Determination of hemodynamic stability & exact mechanism of MR • Medication: afterload reduction diuretics, sodium nitroprusside & nitrates in no hypotension • Intra-aortic balloon counterpulsation (IABP) in hemodynamic compromise acute mitral regurgitation • Emergency surgical intervention is the treatment of choice for papillary muscle rupture • MV repair ดีกว่า Replacement ในกรณีไม่มี papillary necrosis • emergency surgery avoided กรณี intermittent MR due to recurrent ischemia angioplasty or coronary artery bypass grafting (CABG) Etiologies, Prevalence, and Mortality* Causes Incidence 78% Mortality 59% Severe mitral regurgitation 6.9% 55% Ventricular septal rupture 3.9% 87% Isolated right ventricular shock 2.8% 55% Predominant left ventricular failure 1.4% 55% Free wall rupture and tamponade Average 60% *Hochman JS, Buller CE, Sleeper LA, Boland J, Dzavik V, Sanborn TA, et al. Cardiogenic shock complicating acute myocardial infarction-etiologies, management and outcome: a report from the SHOCK Trial Registry. SHould we emergently revascularize Occluded Coronaries for cardiogenic shocK. J Am Coll Cardiol 2000;36(3 Suppl A):1063-70. Left Ventricular Aneurysm • a localized area of myocardium with abnormal outward bulging and deformation during both systole and diastole • approximately 3-15% • Risk factors: female, total occlusion of the LAD artery, single-vessel disease & absence of previous angina • 80% anterolateral wall (asso. CTO of LAD) Left Ventricular Aneurysm • ECG ST elevation persists several weeks after AMI & same leads showing the acute infarct • Echocardiography 93% sensitivity & 94% specificity • cardiac catheterization standard for Dx Left Ventricular Aneurysm Inferior wall aneurysm Left Ventricular Aneurysm • small or clinically insignificant aneurysms conservative, close follow-up • Medical therapy: angiotensin-converting enzyme (ACE) inhibitors reduce afterload, infarct extension & LV remodeling • Anticoagulation severe LV dysfunction and/or thrombus in the LV or aneurysm • Surgical resection: if severe heart failure, ventricular tachyarrhythmias refractory to medical treatment, recurrent thromboembolism Left ventricular mural thrombus • anterior wall infarcts • 20-40% (60% in large anterior-wall AMIs, not treated with anticoagulant therapy) • high risk of systemic embolization (Anticoagulant therapy ↓ rate of embolic events by 33% เทียบกับไม่ได้ anticoagulation) • most common presentation Stroke (within the first 10 days after AMI) Left ventricular mural thrombus • Transthoracic echocardiography modality of choice (92% sensitivity, 88% specificity) • Management heparin treatment followed by oral warfarin therapy for 3-6 months, lifelong anticoagulation if a mural clot persists. Left ventricular mural thrombus Apical LV thrombus Pericarditis • ≈10%, ภายใน 24-96 hr • inflammation of pericardial tissue overlying infarcted myocardium • severe chest pain (pleuritic) & pericardial friction rub • ECG diffuse ST-segment ↑ in all or nearly all of leads • Echocardiography may reveal a small pericardial effusion Pericarditis & Dressler syndrome • Treatment aspirin & NSAIDs • Colchicine in recurrent pericarditis • Post-MI syndrome (Dressler syndrome) autoimmune process, fever, chest pain, signs & symptoms of pericarditis เกิด 2-3 weeks after AMI. • incidence 1-5%, ลดลงหลังมีการรักษาด้ วย thrombolysis และ coronary angioplasty • Management: hospitalization & observation for any evidence of cardiac tamponade, rest, NSAIDs, and/or steroids