PEBC MCQ study guide: Cardiovascular Disorders

Providing Care – Clinical Care

Hypertension, dyslipidemia, heart failure, atrial fibrillation, ACS, and VTE.

Hypertension

Hypertension Canada's 2025 guideline changed the diagnostic model: hypertension is now diagnosed from an average of properly measured OUT-OF-OFFICE readings (home BP monitoring or ambulatory BP monitoring) at a threshold of ≥130/80 mmHg, replacing the older office-based ≥140/90 approach as the primary diagnostic pathway. Office readings remain useful but are now considered less reliable due to white-coat and masked hypertension effects.

Treatment targets: for most adults, a systolic target of <130 mmHg is now recommended (tightened from the previous <140 mmHg general target), reflecting SPRINT-trial-era evidence that intensive control reduces cardiovascular events. Diabetic patients are also managed toward this same intensive target.

First-line pharmacotherapy (uncomplicated hypertension, no compelling indication):

Thiazide/thiazide-like diuretics (chlorthalidone, indapamide preferred over hydrochlorothiazide for outcome evidence)
Long-acting calcium channel blockers (amlodipine)
ACE inhibitors or ARBs (not routinely combined together — combination increases hyperkalemia/AKI risk without added benefit)
Beta-blockers are NOT first-line for uncomplicated hypertension in patients over 60 (less effective at stroke prevention) but remain first-line when a compelling indication co-exists (post-MI, HFrEF, rate control in AFib).

Compelling indications drive drug selection: diabetes with albuminuria or CKD with proteinuria → ACE inhibitor/ARB; HFrEF → ACE inhibitor/ARB (or ARNI) + beta-blocker + MRA + SGLT2 inhibitor; post-MI → beta-blocker + ACE inhibitor.

Most patients require 2+ agents to reach target — combination therapy (often a single-pill combination) should be considered from the outset rather than sequential monotherapy titration, especially when starting BP is ≥20/10 mmHg above target.

Dyslipidemia

Statins remain first-line for both primary and secondary cardiovascular prevention. Intensity is chosen by risk category (Framingham Risk Score or equivalent), not by a fixed LDL target alone, though an LDL-C <2.0 mmol/L (or ≥50% reduction) is a common practical treatment goal for high-risk/secondary-prevention patients.

Statin intensity:

High-intensity: atorvastatin 40–80 mg, rosuvastatin 20–40 mg
Moderate-intensity: atorvastatin 10–20 mg, rosuvastatin 5–10 mg, simvastatin 20–40 mg

Add-on therapy when LDL remains above target on maximally tolerated statin: ezetimibe first (blocks intestinal cholesterol absorption via NPC1L1), then a PCSK9 inhibitor (evolocumab, alirocumab) for very-high-risk patients not at goal.

Key interaction to know cold: simvastatin and atorvastatin are CYP3A4 substrates — strong CYP3A4 inhibitors (clarithromycin, erythromycin, itraconazole, ketoconazole, ritonavir) significantly raise statin levels and myopathy/rhabdomyolysis risk. Simvastatin is contraindicated with strong CYP3A4 inhibitors; the statin should be held or switched (rosuvastatin and pravastatin are not significantly CYP3A4-metabolized and are safer alternatives during a short antibiotic course).

Heart Failure

HFrEF (LVEF ≤40%) is managed with the "four pillars" of guideline-directed medical therapy (GDMT), all four started and up-titrated as tolerated, not sequentially added only after failure of the previous drug:

ARNI (sacubitril/valsartan) preferred over ACE inhibitor/ARB alone when feasible (a 36-hour washout is required when switching from an ACE inhibitor to an ARNI, to avoid overlapping bradykinin-mediated angioedema risk)
Evidence-based beta-blocker (bisoprolol, carvedilol, or metoprolol succinate — NOT metoprolol tartrate)
Mineralocorticoid receptor antagonist (spironolactone, eplerenone) — monitor potassium and renal function closely
SGLT2 inhibitor (dapagliflozin, empagliflozin) — benefit is independent of diabetes status

The Canadian Cardiovascular Society/Canadian Heart Failure Society's 2025 focused update extended SGLT2 inhibitor and broader GDMT-style recommendations to HFmrEF and HFpEF (LVEF >40%), populations that previously had comparatively little proven pharmacotherapy — SGLT2 inhibitors now have a strong recommendation across the full LVEF spectrum.

Loop diuretics (furosemide) manage congestive symptoms but do not alter mortality — they are titrated to euvolemia, not given as a fixed pillar dose.

Atrial Fibrillation & Anticoagulation

Stroke risk in non-valvular AFib is stratified with CHADS-65 (simplified Canadian approach) or CHA2DS2-VASc: essentially, any patient ≥65 years, or younger with a risk factor (prior stroke/TIA, hypertension, heart failure, diabetes), warrants oral anticoagulation.

Direct oral anticoagulants (DOACs — apixaban, rivaroxaban, dabigatran, edoxaban) are preferred over warfarin for most non-valvular AFib patients (comparable or better efficacy, lower intracranial bleeding risk, no routine INR monitoring). Warfarin remains necessary for mechanical heart valves and moderate-to-severe mitral stenosis (valvular AFib) — DOACs are contraindicated there.

Renal dosing matters heavily on the exam: apixaban dose reduction (5 mg BID → 2.5 mg BID) applies when 2 of 3 criteria are met (age ≥80, weight ≤60 kg, SCr ≥133 µmol/L); dabigatran and other DOACs generally require CrCl-based dose adjustment or avoidance at low CrCl.

Rate vs. rhythm control: rate control (beta-blocker or non-dihydropyridine CCB) is first-line for most patients; rhythm control (antiarrhythmics or ablation) is reserved for symptomatic patients or those who don't tolerate rate control.

Acute Coronary Syndrome & Antiplatelet Therapy

Dual antiplatelet therapy (DAPT) — ASA plus a P2Y12 inhibitor (ticagrelor, prasugrel, or clopidogrel) — is standard after ACS/PCI, typically continued for 12 months before de-escalating to ASA monotherapy (duration individualized by bleeding vs. ischemic risk).

Ticagrelor and prasugrel are generally preferred over clopidogrel post-ACS due to more potent, less variable platelet inhibition (clopidogrel requires CYP2C19 activation and is subject to genetic non-responders), but clopidogrel remains preferred when bleeding risk is high or with concurrent anticoagulation (triple therapy).

Triple therapy (DOAC + single antiplatelet, usually clopidogrel) rather than the older DOAC+DAPT combination is now favoured for AFib patients after PCI, to reduce bleeding while maintaining stent thrombosis prevention.

Venous Thromboembolism

DOACs (apixaban, rivaroxaban) are first-line for most uncomplicated DVT/PE, without the need for initial parenteral bridging for apixaban/rivaroxaban (both use an initial higher-dose loading phase instead). Dabigatran and edoxaban still require 5–10 days of initial parenteral anticoagulation (LMWH) before starting.

Extended/prophylactic-dose anticoagulation is considered for unprovoked VTE after the initial treatment course, balanced against bleeding risk. LMWH remains preferred over DOACs in cancer-associated thrombosis in many patients, though DOACs are increasingly used in this setting too.

High-yield points

Hypertension Canada 2025: diagnose from out-of-office readings ≥130/80 mmHg; systolic target <130 mmHg for most adults.
Simvastatin/atorvastatin + strong CYP3A4 inhibitor (clarithromycin, itraconazole) = major myopathy/rhabdomyolysis interaction; switch to rosuvastatin or hold the statin.
HFrEF four-pillar GDMT (ARNI/ACEi/ARB + beta-blocker + MRA + SGLT2i) is started together, not sequentially — SGLT2i benefit now extends to HFmrEF/HFpEF per the 2025 CCS/CHFS update.
CHADS-65: virtually every AFib patient ≥65, or younger with a risk factor, needs anticoagulation — DOACs preferred except in valvular AFib (mechanical valve, moderate-severe mitral stenosis).
Apixaban dose reduction to 2.5 mg BID requires 2 of 3: age ≥80, weight ≤60 kg, SCr ≥133 µmol/L.

Guideline references

Hypertension Canada 2025 Guideline
Canadian Cardiovascular Society (CCS) Dyslipidemia Guidelines
CCS/Canadian Heart Failure Society 2025 Focused Update
CCS Atrial Fibrillation Guidelines
Canadian Cardiovascular Society ACS Guidelines
Thrombosis Canada Clinical Guides