Maintaining pace with rapidly changing clinical practice guidelines presents a perpetual challenge for health care professionals. This article is part 1 in a 3-part series offering busy clinicians a succinct summary of key recommendation updates published in 2023 in various fields relevant to primary care, such as cardiac care, stroke management, and diabetes treatment. These guideline changes, presented in an easily understandable format, are intended to help family physicians adapt the latest evidence-based advice into their clinical decision making swiftly, thus elevating patient care quality.

The American College of Cardiology (ACC) recommends consideration of sodium-glucose cotransporter-2 inhibitors (SGLT2Is) to reduce risks of hospitalizations and cardiovascular death in patients who have heart failure (HF) with preserved ejection fraction (EF) (class 2a recommendation).1 In patients with HF whose EF is below 55%, consider adding angiotensin receptor–neprilysin inhibitors for similar benefits, and mineralocorticoid receptor antagonists to enhance diastolic function (class 2b recommendation), acknowledging sex-specific responses.1

The Canadian Cardiovascular Society (CCS) has identified 5 HF phenotypes—wet, de novo, worsening, cardiorenal, and frail—to guide personalized treatment (no level of evidence provided).2 The approach includes using diuretics for fluid overload in patients with the wet HF phenotype; employing guideline-directed medical therapy tailored to the characteristics of de novo HF; optimizing guideline-directed medical therapy for patients with worsening HF; using careful volume assessment for patients with cardiorenal HF; and titrating drugs gently for patients with the frail HF phenotype.

The American Heart Association has recommended several complementary and alternative medicines for management of heart failure (no level of evidence provided).3 The authors suggest supplementation with coenzyme Q10, omega-3 fatty acids, and l-carnitine to potentially lower mortality risk and improve heart function. Coenzyme Q10 might also reduce hospitalization risk, enhance exercise capacity, improve New York Heart Association functional classification, and reduce atrial fibrillation episodes. Supplementing deficiencies in thiamine, vitamin C, and vitamin D has been associated with improved cardiac function and reduced risk. Mind-body activities such as yoga and tai chi are associated with improvements in exercise capacity and quality of life and with reductions in inflammatory marker levels.

The ACC recommends reevaluating the need for β-blockers 1 year after myocardial infarction (MI) in patients without HF, arrhythmias, or uncontrolled hypertension (weak recommendation, level B evidence from nonrandomized trials and meta-analyses).4 Evidence is emerging that β-blockers provide limited benefit in individuals with normal left ventricular function and might have adverse effects such as fatigue and depression. Based on randomized controlled trial results, the ACC also recommends considering ranolazine for patients with chronic coronary disease experiencing persistent angina despite antianginal therapies (strong recommendation, level B evidence).4 Ranolazine has been found to decrease anginal episodes.4

The CCS recommends individualizing dual antiplatelet therapy in patients at high risk of bleeding (weak recommendation, moderate-quality evidence).5 Consider a shortened duration of 1 to 3 months for dual antiplatelet therapy following percutaneous coronary intervention in patients at high risk of bleeding. This recommendation aims to balance risks of bleeding and ischemia. Following this shorter course, the CSS recommends maintenance with a single antiplatelet agent, preferably a P2Y12 inhibitor.

The Patients, Experience, Evidence, and Research (PEER) panel of experts recommends screening adults for primary prevention of dyslipidemia no more than every 5 years, and ideally every 10 years (no grade of evidence provided).6 In its latest guideline the PEER team notes that individuals’ lipid levels change minimally in a year—typically less than 1%. Over a decade this change is generally less than 10%, a shift largely indistinguishable due to the 10% to 20% variability in single test measurements. Given this, coupled with the more pronounced effect of aging on cardiovascular risk, frequent lipid tests add limited value to refining risk assessments for cardiovascular disease.

The CCS introduces a novel classification system for acute MI.7 The classification system used for MI is based on severity of tissue injury and identifies 4 progressive stages of myocardial damage: aborted MI; MI with substantial cardiomyocyte necrosis but no microvascular injury; MI with both cardiomyocyte necrosis and microvascular obstruction; and MI with the combination of cardiomyocyte necrosis, microvascular obstruction, and reperfusion hemorrhage. The primary goal of this system is to enhance patient risk assessment, patient management, and research by focusing on specific stages and severity of tissue injury in patients with MI.

The seventh edition of the Canadian Stroke Best Practice Recommendations for Acute Stroke Management endorses considering tenecteplase as an alternative to alteplase for thrombolysis in patients with acute ischemic stroke within 4.5 hours of symptom onset (strong recommendation, moderate-quality evidence).8 The recommended dose of tenecteplase in patients experiencing a stroke is 0.25 mg/kg up to 25 mg maximum, administered as a single intravenous bolus over 5 seconds (this differs from dosing for patients with MI or pulmonary embolism). Two reviews published in 2022 and 2023 and a retrospective analysis published in 2023 suggest tenecteplase might have comparable or superior efficacy and safety profiles compared with alteplase in patients with acute stroke thrombolysis.9-11 A key practical advantage of tenecteplase is its single bolus dosing in contrast to alteplase’s 1-hour infusion requirement. However, uncertainty remains around optimal tenecteplase dosing, with higher doses (eg, 0.4 mg/kg) potentially increasing systemic hemorrhage risk.8

The American Diabetes Association strongly recommends adding a glucagonlike peptide-1 receptor agonist (GLP1-RA) to medication regimens of patients with type 2 diabetes who are already taking insulin (grade A recommendation).12 This aligns with earlier guidance13 published by Diabetes Canada in 2020. This approach is associated with improvements in blood glucose control and weight management and with a reduced risk of hypoglycemia compared with simply increasing insulin dosage. Multiple trials have demonstrated that combining GLP1-RAs (eg, liraglutide) with insulin leads to greater reductions in hemoglobin A1c (HbA1c) levels and in body weight compared with insulin alone, without increasing hypoglycemia risk. While primarily indicated for patients with type 2 diabetes, GLP1-RAs have also shown some benefits in patients with type 1 diabetes, including modest reductions in HbA1c levels, weight reduction, and lower insulin requirements.

Diabetes Canada defines complete remission of type 2 diabetes as achieving HbA1c levels in the normal range (<6.0%) for at least 1 year without use of glucose-lowering medications (grade D recommendation, consensus).14 For remission induction in selected adults with obesity (body mass index scores ≥30 kg/m2), Diabetes Canada recommends an intensive lifestyle intervention consisting of a very-low-calorie diet with meal replacement providing 800 to 850 kcal per day for 3 to 5 months, along with 240 to 420 minutes of physical activity per week (grade A recommendation, high-quality evidence).14 Bariatric metabolic surgery is recommended for qualifying patients with body mass index scores greater than or equal to 35 kg/m2 (grade A recommendation, high-quality evidence).14 Long-term monitoring every 3 to 6 months is advised to assess remission durability.

New guidelines from Diabetes Canada redefine the threshold for hypoglycemia as a blood glucose level less than 3.9 mmol/L, lower than the previous <4.0 mmol/L criterion (grade D recommendation, consensus).15,16 A 3-level classification system for hypoglycemia is introduced: level 1 (blood glucose level 3.0-3.9 mmol/L), level 2 (<3.0 mmol/L), and level 3 (severe cognitive impairment requiring third-party assistance). For level 3 events the guidelines strongly recommend glucagon treatment, preferably the intranasal glucagon formulation (grade A recommendation).15,17 Frequent mild (level 1) hypoglycemia is highlighted as a risk factor for impaired awareness of hypoglycemia. The guidelines advise routinely screening for and addressing this complication in insulin-treated patients with diabetes through structured education and adjustments to glycemic targets and therapies as needed (grade D recommendation, consensus).15