Cardio Flashcards
How Do CAD Patients Present?
Ischemic cascade – with increasing ischemic time:
1. Blood flow changes (can be seen on myocardial perfusion)
2. Diastolic, then systolic dysfunction (wall motion abnormalities)
3. ECG changes
4. Symptoms
5. Myocardial necrosis
Diagnostic Tests for CAD
Functional
Non-invasive stress tests:
– STRESS = exercise,
drugs (inotropes,
vasodilators)
– TEST = ECG, ECG+echo,
ECG+nuclear
STRESS: pick exercise whenever possible!
– Provides prognostic info: e.g. duration of exercise, METs
– Not possible if physical limitations or contraindications
(e.g. critical aortic stenosis)
- TEST: consider functional imaging (e.g. nuclear) if:
– Cannot accurately assess for ischemia on ECG - LBBB, paced rhythm, preexcitation, significant ST changes at
rest à the ECG is not interpretable in these cases
– RBBB interpretable generally
– Need specific anatomic correlation (e.g. prior
revascularization)
Structural
– Coronary angiography
– CT coronary
angiography
Absolute Contraindications to EST
- Acute MI (within 2 days)
- Ongoing unstable angina
- Uncontrolled hemodynamically-significant
arrhythmia - Active endocarditis
- Symptomatic severe AS
- Decompensated heart failure
- Acute PE, pulmonary infarction, DVT
- Acute myocarditis, pericarditis
- Acute aortic dissection
- Physical limitations
EST Results
Positive test
– ≥ 1mm STE
– ≥ 1 mm STD (horizontal or
downsloping)
High risk features*
– Duke Treadmill Score -11 or less
– <5 METs achieved
– Low threshold angina / ischemia
– STE
– Severe STD ≥ 2mm
– Ischemia on ≥ 5 leads
– Ischemia ≥ 3 mins into recovery
– Abnormal BP response [failure to
achieve SBP>120, drop in BP >10,
drop below baseline]
– Ventricular arrhythmia
Myocardial Perfusion Imaging
Radioactive tracer (e.g. 99mTc) is used that distributes into myocardium proportionally
with blood flow
* SPECT imaging detects decay of tracer
* Stress = exercise vs. pharmacologic (e.g. dipyridamole)
– Pharmacologic stress based on coronary perfusion mismatch after vasodilation
* dipyridamole (aka persantine) most commonly used for nuclear stress, less commonly adenosine
* Dobutamine used commonly for stress echocardiography
– Diseased coronary vessels are already maximally dilated and develop perfusion mismatch
– False negatives can be seen:
- Drug interactions with dipyridamole (caffeine, theophylline – hold before test!)
*
Severe flow limiting triple vessel or left main disease (“balanced” ischemia so no perfusion mismatch
detected) - Consider as a potential first-line test if patient cannot complete ECG stress test
- Contraindications: active or severe asthma/COPD, as dipyridamole can cause
bronchospasm
– Reversal agent for dipyridamole is aminophylline
Coronary Artery
Calcium (CAC) Score from CT
CAC scoring is recommended for further risk
stratification of intermediate risk (FRS 10-19%)
asymptomatic patients aged > 40 who are not
candidates for statin based on other risk
factors
- Can consider CAC scoring for low risk patients
with family hx premature CV Dz and genetic
dyslipidemia
- CAC score > 100 is basically a statin indicated
condition; start therapy regardless of FRS
Coronary CT Angiography (CCTA)
Procedure specifics:
– Low dose CT with beta blockade +/- IV nitro given (HR target <60), breath hold
Indications:
– Diagnosis of CAD for low to intermediate pre-test prob patients
– Risk stratification in patients with stable CAD
Contraindications:
– ACS
– Severe structural heart disease (AS or HCM)
– Usual CT precautions: Contrast Allergy, Renal Failure, Pregnancy
Treatment of Chronic Stable CAD
General Principles
- Treat symptoms with medical therapy first
- Consider revascularization if refractory symptoms, high risk structural disease (e.g. LM
disease), LV dysfunction, severe MR
Optimal Medical Therapy (OMT) is non-inferior to revascularization (PCI/CABG) for
patients with Stable CAD
- ALL patients with CAD:
– Commence medical treatment for CAD
– Aspirin + statin for evidence of coronary atheroscerosis regardless of the
modality of diagnosis
– Clopidogrel can be used as SAPT if ASA intolerant
Antianginal (symptomatic benefit):
– Beta blockers: reduce HR/contractility, indicated
for most patients*
– CCBs: reduce HR/contractility (non- dihydropyridine, beware if LVEF<40%), reduce
preload (dihydropyridine)
– Nitrates: venodilate, reduce LVEDP
– Others: ranolazine (calcium modulator that
reduces angina, just so you’re aware of but use in
Canada is rare)
Disease modifying therapies:
– ACE inhibitors: HTN, T2DM, LVEF <40%, CKD, can
be considered for all for vascular protection
– Beta blockers: LVEF<40%
* *If no previous MI and LVEF >50 = use of BB therapy
does not ↓ MACE, in absence of other indication for
BB (eg for control of HTN or rapid afib) – ACC/AHA
2023
– CAD + DM: SGLT2i or GLP1RA
– Hypertension, dyslipidemia, diabetes management
Revascularization - PCI vs. CABG
In general, invasive angiography
should be considered for:
- High risk features on non- invasive testing
- Medically refractory
symptoms
In general PCI is less invasive and useful to
treat symptoms. CABG preferred if:
* L main disease (>50% occlusion)
* Multivessel disease with diabetes
* Multivessel disease with LV
dysfunction/CHF
For MCQs:
* Conflicting stroke data
* Less repeat revascularization with CABG
* Survival with CABG in highly select
scenarios
* “Team-based decision” beyond scope of
GIM
Immediate Medical Management of ACS
The ACS “cocktail”
* Antiplatelet: ASA + 2nd agent (ticagrelor, clopidogrel, prasugrel)
– Loading doses à ASA (160 mg CHEWED), Ticagrelor (180 mg), Prasugrel (60mg) Clopidogrel
(300-600 mg)
* Ticagrelor C/I if previous intracranial hemorrhage, prasugrel C/I if ANY prior TIA/Stroke
* If thrombolysis à ASA + Clopidogrel (NO TICAGRELOR OR PRASUGREL)
– Maintenance doses à ASA (81 mg OD), Ticagrelor (90 mg q12h), Clopidogrel (75 mg OD)
Anticoagulation: UFH or LMWH or Fondaparinux
– Continued for 48 hours until discharge or 8 days, stop if revascularized
Antianginals: beta-blocker, cautious administration, within 24 hours for stable
patients.
Reperfusion Therapy – STEMI
Principle: achieve coronary patency in ALL
patients presenting <24h from symptom
onset, or with ongoing symptoms
- Options:
– Primary PCI
– Fibrinolysis/pharmaco-invasive (“drip & ship”) - Primary PCI > fibrinolysis:
– if timely - PCI capable hospital à FMC-to-balloon time <90 min
- Non-PCI capable hospital à FMC-to-balloon time <120 min
FMC = First Medical Contact à ER triage if walk-in, or EMS arrival if 911
– if later presentation (12-24h of symptom onset)
– if cardiogenic shock
- Fibrinolysis indicated if PCI is not readily available (>120min)
- Pharmaco-invasive strategy superior to rescue PCI: Drip (give lysis)
then ship (send immediately to PCI centre for angiogram/PCI
within 3-24 hours)
– If fibrinolysis à should be administered within 30 minutes of FMC
– If Fibrinolysis à PCI should occur within 24 hr.
– Timing of fibrinolysis à the earlier, the better, but can be given up to
24h after onset of chest pain w STE
The Second Antiplatelet… CCS 2023
Ticagrelor preferred (conditional)
– vs clopidogrel greater efficacy, no
increased bleeding risk
If patient is High bleeding risk
– DAPT for 1-3 months non-inferior to
longer durations
* “practice point” – if stepdown to SAPT
choose P2Yinhibitor over ASA
* Step-down to SAPT should incorporate
cardiologist – (eg) avoid if high risk PCI or
hx stent thrombosis
CCS 2023 Pearls… ACS à CABG
If you strongly suspect CABG will be required, can withhold P2Yi prior to Angiogram
even if expected delay >24h post ACS
- Stopping P2Yi prior to CABG
– Limited evidence… “multidisc team” to decide, hold 2-7d pre-op - Suggest hold Ticagrelor 2-3 days rather than 5-7d [weak, conditional]
- Postop Antiplatelet Regimen
– Off-pump – favour DAPT, with ASA + ticagrelor/prasugrel over ASA + Clopidogrel
– On-pump – favor SAPT
– AFIB? – consider OAC monotherapy
The Second Antiplatelet… Nuances
Ticagrelor is contraindicated if history of:
– intracranial hemorrhage
– active pathological bleeding
– moderate-severe hepatic impairment
– combinations with CYP34A inhibitors (ketoconazole, clarithromycin, ritonavir)
– Should consider avoiding in patients with evidence of heart block or bradycardia.
– Dose: 180mg load then 90 mg bid x 12 months then 60mg bid thereafter
- Prasugrel is contraindicated if:
– active bleeding
– prior TIA/stroke [even ISCHEMIC stroke]
– hypersensitivity reaction – Dose: 60mg load then 10mg daily (reduce to 5mg if <60kg) - Ticagrelor & Prasugrel have NOT been adequately evaluated in the setting of
fibrinolysis in STEMI à Use clopidogrel pre-PCI
Reperfusion Therapy - NSTE-ACS
Timing & risk stratification are the major differences vs. STEMI
1. Risk stratify using clinical judgment + risk scores (TIMI, GRACE)
- Do not memorize these, but understand what factors involved
- Int/high risk patients: early invasive strategy (angiogram within
48hr)
- Early invasive reduces risk of rehospitalization for ACS but NO
mortality benefit - Low risk patients and/or unclear diagnosis: non-invasive testing
(often with functional imaging) reasonable to determine
benefit of invasive strategy
PCI options
- Plain-Old-Balloon-Angioplasty (POBA)
– Rare - Bare metal stent (BMS) – rarely used
– Endothelialize quickly = lower risk of stent thrombosis after 4+ weeks
– But…higher risk of re-stenosis - Drug eluting stent (DES) – standard of care
– Elute anti-proliferative agents
– Lower rates of restenosis vs. BMS = can be used in smaller vessels, CABG grafts
– But…take longer to endothelialize - Drug coated balloon (DCB)
– Expand a blood vessel and deliver antiproliferative agents (e.g. Paclitaxel) without delivering
a stent
– Useful for in-stent restenosis (ISR), bifurcating/branch lesions, buying time for definitive
treatment
Stents and DAPT Durations(without AF)
POST ACS (STEMI or NSTEMI/UA): Aim for 12 months of DAPT
– ACS DAPT= ASA + Ticagrelor 90 BID or Prasugrel 10 OD (preferred over ASA+Clop)
* NEW CCS 2023: If High Risk of Bleeding with PCI post ACS, can de-escalate to SAPT after 1-3 months
of DAPT OR de-escalate from a more potent second antiplatelet (i.e. change from ASA+ticagrelor to
ASA+clopidogrel)
* Reassess bleeding at 1 year.
– If HIGH RISK bleed: SAPT ASA 81 or Clopidogrel 75
– If LOW RISK bleed: Continue DAPT - Good evidence for up to 3 years (DAPT trial)
DAPT After 12 months: Suggest ASA + one of:
* Ticagrelor (60 mg po bid) (reduced dose, not standard dose)
* Clopidogrel (75 mg po daily)
* Prasugrel (10mg po daily) (weaker recommendation that others for extended therapy)
Non-ACS situations (ELECTIVE PCI)
* High Risk of Bleeding: Elective PCI DAPT = ASA 81+ Clopidogrel 75
– BMS = DAPT for 1 month then SAPT with ASA 81 or Clopidogrel 75 indefinitely
– DES = DAPT for 3 months then SAPT with ASA 81 or Clopidogrel 75 indefinitely
* Not at high risk of bleeding: DAPT for 6 months, then reassess
– If High Risk thrombotic events: extend DAPT up to 3 yrs
– If not at high risk of thrombosis or if now at high risk bleeding: SAPT (ASA or Clop)
CCS 2023 Antiplatelet Guideline:AFIB + Antiplatelets
- Antiplatelet and anticoagulation (i.e. patient on OAC for atrial
fibrillation)
– Dual pathway (clopidogrel+OAC) recommended over previous
strategy of triple therapy for 1-30 days in most patients (but the small
text says they need to receive 1 dose of ASA at PCI time, so it is like
they only received 1 dose of triple therapy)
– OAC monotherapy preferred over OAC+aspirin in stable CAD (from the
AFIRE trial which showed rivaroxaban+ASA had more bleeding with no
reduction on ischemic events compared to rivaroxaban alone)
Complex PCI
Complex PCI = patient that you would be less willing to do a shorter duration/less potent regiment of DAPT.
Just need 1:
* Left main
* 3 vessels
* 3 lesions
* 3 stents
* >60mm stent
* Bifurcation stents
* Bypass graft PCI
* Atherectomy, CTO
procedure
Periop Mgmt - Stents and DAPT
Elective Non-Cardiac Surgery
* BMS – Delay surgery for at least 1 month post PCI
* DES – Delay surgery for at least 3 months post PCI
Semi-Urgent Non-Cardiac Surgery
* BMS – Delay surgery for at least 1 month post PCI*
* DES – Delay surgery for at least 1 month post PCI*
*weak recommendation, low quality evidence – individualize as semi-urgent sx usually can’t be delayed 1 month
Pre-Op
* Hold Clopidogrel and Ticagrelor 5-7d preoperatively
– 5-7 days if neuraxial anesthesia or very high risk bleeding, speak to anesthetist and surgeon
* Hold prasugrel 7-10d preoperatively
* Continue ASA perioperatively “whenever possible”
Post-Op
- Restart DAPT post-op as soon as deemed safe by surgical team
Post-MI Complications
- Heart failure
- Arrhythmias
– Tachy: Atrial, ventricular
– Brady: Heart block (esp. inferior MI) - Mechanical complications
– Papillary muscle dysfunction and acute MR
– Ventricular septal rupture
– Free wall rupture
– RV infarction (esp. inferior) - Pericarditis
– Post MI pericarditis = Early (5d) vs. delayed [Dressler syndrome] (2-8wks)
– Fever, pleuritic chest pain, pericardial rub and/or pleural effusion; Rx is
high dose ASA + colchicine
Chronic Management/Risk factors
Initiate BEFORE Discharge
* High potency statin
* ACEi, BB
* Identify +/- optimize diabetes
* Influenza vaccine
* Smoking Cessation Therapy [see Resp Lecture BONUS slides]
* Cardiovascular Rehab
* Driving restrictions [NEW! CCS 2023 Guidelines]
Diagnostic approach Cardiomyopathies
& Heart Failure
All patients with heart failure (regardless of LVEF): ECG,echocardiogram, CBC, lytes, creatinine, ferritin, TSH, troponin, BNP
- Common etiologies: ischemic heart disease (perform ischemia testing if known CAD or risk factors), HTN/LVH, tachyarrhythmias,
valvular disease
– Non-invasive imaging to rule in/out CAD should be considered
– Invasive (coronary angiography):
* Recommend if HF with angina / Ischemic symptoms, likely to be good candidates for
revascularization
* Consider if: LVEF <35, at risk of CAD, irrespective of angina, likely good candidates for
revascularization
* Consider if: systolic HF and non-invasive coronary perfusion testing consistent with high
risk
Diagnostic approach Cardiomyopathies
& Heart Failure- continued
Less common etiologies (i.e. non-ischemic):
* Familial dilated cardiomyopathy
* Genetic (HCM, ARVC, hemochromatosis)
* Drugs /toxins (alcohol, cocaine,
chemotherapy)
* Pregnancy (Postpartum cardiomyopathy)
* Inflammatory (myocarditis, sarcoid)
* Endocrine (pheochromocytoma, Cushing)
* Nutritional (thiamine deficiency / beriberi,
selenium deficiency)
* Infiltrative (amyloid, Fabry)
Workup for non ischemic cardiomyopathy
– Good History
* Testing directed by history (eg) genetics if family
history
– Cardiac MRI for most with non-ischemic
cardiomyopathy
(If available)
* To help rule out infiltrative, ARVC
Acute HF Management
In general
– Establish Diagnosis ASAP
(guidelines say <2h after contact in ED)
– Start with ABCs, IV O2 Monitor (IOM)
– Focused history: dyspnea, fatigue, edema
– Focused physical: congestion, valvular dz,
perfusion
– CBC, lytes, urea/Cr, gluc, BNP, Tn
– ECG, CXR
– Echo (w/in 48h)
– Consult CCU/Cardiology
– Consider potential etiologies or triggers for
decompensation
* Ischemia, HTN, Anemia, rapid afib, infection,
med or diet non adherence, NSAIDs, PE, thyroid…
Long-term Management of HFrEF
Establish etiology
Practically: Hx/PE/labs +
* Echocardiogram (r/o non-myocardial causes)
* BNP: 2017 CCS recommends BNP if diagnosis unclear and for prognosis
* Assess for CAD (very often coronary angiography)
* CMRI for non ischemic etiologies
Quantify degree of disability
NYHA classification (I-IV)
* Allows clinician to track progress
* Becomes important for therapy considerations
Risk factor modification & lifestyle interventions
* Exercise (flexibility, aerobic, +/- resistance)
* Salt restriction (<2-3g/d) à SODIUM-HF trial 2022 showed that strict salt restriction <2g/day did not improve HF related
hospital visit or CV death
* +/- fluid restriction (<2L/d)
* Smoking cessation
* EtOH avoidance
* Discuss Driving Safety (see bonus slides)
Treat HF-associated comorbidities (see later)
Multidisciplinary care model
Early advanced care planning discussions
Interventional therapy considerations
* ICD, CRT (see later)
* Surgery / percutaneous treatment of functional MR (see later)
* Revascularization in ICM
Advanced HF
* Really low EF, ++hospitalizations, NYHA IV, organ dysfunction, cardiac cachexia, high 1-year mortality, bad CPET performance…
* May need: Mechanical circulatory support (eg) VAD, Transplant workup, or palliative care
Once stabilized, reassess at least annually with clinical assessment + LVEF assessment
Revascularization and ischemic cardiomyopathy
If choosing an option for revascularization for ischemic cardiomyopathy, CABG would likely lead to improved outcomes compared to PCI with the available evidence. However, optimizing
medical therapy is paramount in ALL patients!
HFrEF Pharmacotherapy
Guideline recommended pharmacotherapy for HFrEF
“Backbone” of HFrEF therapy now QUADUPLE Tx
* ARNI / ACEI/ARB
* MRA
* SGLT2i (even if not diabetic!)
* BB [only start when euvolemic and
hemodynamically stable]
- Avoid CCBs with LVEF < 40% (amlodipine ok for HTN)
- Do not start BBs on NYHA IV patients
- ARNI initiation requires 36h “washout period” after ACEI use
ARNI in clinical practice:
Start ARNI: Hospitalized w new dx HFrEF
Switch to ARNI if:
- Hospitalized for HF on ACE/ARB
- Symptomatic (NYHA2+) despite max ACE/ARB
And CONSIDER :
- Sinus rhythm and HR >70: Ivabradine
- Recent HF hospitalization: Vericiguat*
- Black pts on optimal GMT: Hydralazine/ISDN
- Unable to take ACE/ARB/ARNI: Hydralazine/ISDN
- Persistent symptoms despite Rx
above or poor rate cntrl with AFIB: Digoxin
Titrate drugs every 2-4 weeks over 3-6 mos then reassess:
-If NYHA 1, LVEF >35, low risk: Continue current mgmt
-If NYHA 1-4, LVEF ≤35 ambulatory: Check out Device therapy guidelines
-If NYHA 3-4, high risk, advanced HF: Advanced care plan, palliation
Refer for advanced HF therapy (LVAD etc)
Important HF Medication Considerations
- Beta blockers
– Use bisoprolol, carvedilol or metoprolol SUCCINATE (extended release; not available in most of Canada)
– NYHA IV patients should be stabilized prior to the initiation of a beta-blocker
– Chronic beta-blocker should be continued in acute heart failure unless patient symptomatic from hypotension or bradycardia - Ivabradine
– Acts on SINUS NODE to reduces heart rate in patients without reducing BP or contractility (need to be in SINUS RHYTHM)
– Maximize dose of beta blocker first, use if hospitalized in last 12 months for CHF + HR > 70 - ACE/ARB/ARNI (Angiotensin receptor neprilysin inhibitor)
– ARB should be used if patient intolerant to ACEI or develops angioedema (although angioedema can still occur with ARBs – rare). ARNI
contraindicated if history of hereditary (familial) or idiopathic angioedema
– When switching from ACE to ARNI, 36 hour washout period important to lower risk of angioedema. No washout required for ARB/ARNI
switch - Vericiguat (Approved but not yet widely available in Canada)
– Novel oral soluble guanylate cyclase stimulator, works by enhancing effects of NO
– VICTORIA trial à NYHA II-IV HF (LVEF <45%) recent hospitalization or IV diuretic therapy - Primary outcome (CV death, HF hospitalization) reduced by 10% vs. placebo
- Better for lower LVEFs
- Well tolerated
- More anemia in the vericiguat group
ICDs in HF
- Primary (low EF) vs. secondary
prevention considerations - Primary prevention devices considered
appropriate after:
– 3m OMT
– 3m post-revascularization
– 40d after MI - Patients should have expected
longevity > 1 year (or considerations
for VAD, transplant) - Caution for patients with NYHA IV, not
expected to improve - ICM, NYHA II-IV, LVEF ≤ 35%
- ICM, NYHA I, LVEF ≤ 30%
- NICM, NYHA II-III, LVEF ≤ 35%
ICDs for 2o prevention
- Cardiac Arrest (VT-VF)
2.Sustained VT in the presence of significant structural heart disease - Sustained VT >48 h post MI or revascularization
no reversible cause - give ICD
ICD systems
Transvenous: most common, lead through
subclavian vein into RV, can pace and defib.
Subcutaneous: devices sits in the axilla,
lower risk of venous stenosis and
endocarditis, shorter battery life, useful for
younger patients. Does not pace!
Cardiac Resynchronization Therapy (CRT)- general principles
- Cardiomyopathy à electromechanical V-V dyssynchrony
- Dyssynchrony à lower SV/CO, more MR, higher filling pressures, worse
functional status, more hospitalizations, more death - Dyssynchrony tends to correspond to abnormal QRSd on ECG
- CRT paces RV and LV to ”Resynchronize”
- Platform options – CRT-D (pacing + defibrillation), CRT-P (pacing only)
- CRT has been shown to reduced HF symptoms, hospitalizations, death
