31: 66-year-old woman with shortness of breath Flashcards
Risk Factors for Coronary Artery Disease…Important modifiable risk factors that can be addressed with the patient include:
diabetes
high blood pressure, whether controlled or uncontrolled
current tobacco use
abnormal lipid levels, particularly high LDL-c and low HDL-c
Risk Factors for Coronary Artery Disease…Key non-modifiable risk factors include:
older age (men over 45, women over 55) family history
Medications for a Patient with Both Diabetes and Hypertension
Angiotensin converting enzyme (ACE) inhibitors
ramipril
Has renal protective effects in diabetics in addition to lowering blood pressure.
Thiazide diuretics
hydrochlorothiazide
Works synergistically with the ACE inhibitor and therefore an effective addition for blood pressure control, though it can also increase blood sugar.
Oral hypoglycemics
metformin
Metformin is a good choice for an oral hypoglycemic given overweight status, although the use of insulin mitigates the metformin advantage of not causing weight gain.
NSAID
aspirin (ASA)
The USPSTF recommends initiating low-dose aspirin use for the primary prevention of cardiovascular disease (CVD) and colorectal cancer (CRC) in adults aged 50 to 59 years who have a 10% or greater 10-year CVD risk, are not at increased risk for bleeding, have a life expectancy of at least 10 years, and are willing to take low-dose aspirin daily for at least 10 years.
The USPSTF recommends the service. There is high certainty that the net benefit is moderate or there is moderate certainty that the net benefit is moderate to substantial.
Adults aged 60 to 69 years with a ≥10% 10-year CVD risk:
The decision to initiate low-dose aspirin use for the primary prevention of CVD and CRC in adults aged 60 to 69 years who have a 10% or greater 10-year CVD risk should be an individual one. Persons who are not at increased risk for bleeding, have a life expectancy of at least 10 years, and are willing to take low-dose aspirin daily for at least 10 years are more likely to benefit. Persons who place a higher value on the potential benefits than the potential harms may choose to initiate low-dose aspirin.
Statins
atorvastatin
First line therapy for lowering LDL cholesterol and reducing ASCVD risk in patients with diabetes.
Physical Exam Findings for Suspected Heart Failure
- -Crackles in the lung bases and dullness to percussion
- -Jugular venous distention
- -Point of maximal impulse (PMI) that is laterally displaced from the mid-clavicular line towards the axillary line
- -S3 from rapid ventricular filling or poor left ventricular functioning
- -Enlarged liver, hepato-jugular reflux (distention of the jugular vein upon manual pressure on the liver), and distention and shifting dullness indicating ascites
- -Lower extremity edema and check pulses
- -Sacral edema
Diastolic heart failure
occurs when signs and symptoms of heart failure are present, but left ventricular function is preserved (ejection fraction >45%). It is caused by impaired LV filling and abnormal LV relaxation and is most commonly related to uncontrolled hypertension. The incidence of diastolic heart failure increases with age and is more common in older women. Diastolic heart failure has recently been renamed ‘heart failure with preserved EF’ (HFpEF), though the two terms are synonymous
Concomitant systolic and diastolic dysfunction
As it turns out, all patients with systolic dysfunction also have concomitant diastolic dysfunction. Therefore, a patient cannot have pure systolic heart failure. On the other hand, certain cardiovascular diseases such as hypertension may lead to diastolic dysfunction without concomitant systolic dysfunction. On average, 40% of patients with CHF have preserved systolic function. These patients have a better prognosis than those with systolic dysfunction.
Pathophysiology of diastolic dysfunction
The left ventricle develops an abnormality of filling and becomes stiffer and noncompliant as the disease progresses. Then there is increased pulmonary vessel pressure during exercise, increased filling pressure and, as left atrial pressure and size increase, congestion. At this point, exercise intolerance increases and clinical signs of failure, particularly dyspnea on exertion (DOE), appear. It’s like a backup in the pump with increasing pressure and leakage resulting. So pulmonary congestion, hepatic congestion and peripheral edema appear.
Differentiating heart failure from non-cardiac conditions in patients with dyspnea
Brain natriuretic peptide (BNP) testing can help differentiate heart failure from non-cardiac conditions in patients with dyspnea. A normal BNP effectively rules out CHF. However, an elevated BNP cannot distinguish diastolic from systolic heart failure.
Interventions to Slow the Progression of Coronary Artery Disease
-glucose control
-BP control
-ASA
-cholesterol control
»Cholesterol control
The ACC/AHA guidelines for cholesterol management recommend that all patients with type 1 or 2 diabetes age 40-75 years old should be on either a moderate-intensity statin, or (if their estimated 10-year ASCVD risk >7.5%) a high-intensity statin.
-weight control
-immunizations
-beta blockers
Management of Stage C Heart Failure
ACE inhibitors represent the mainstay of management of systolic heart failure. They also have key roles in the management of both diabetes and coronary artery disease.
ARBs have also been demonstrated to improve mortality in patients with systolic failure. Given that they are more expensive than ACE inhibitors, they are typically reserved for patients who can’t tolerate ACEs due to side effects such as cough. An ACE inhibitor should not be combined with an ARB, due to evidence of harms when they are combined.
Digoxin in randomized trials has demonstrated improved symptoms and reduced hospitalizations in patients with NYHA class II, III, and IV systolic failure. Physicians need to be cautious about digoxin toxicity, particularly in patients with renal insufficiency.
Loop diuretics such as furosemide (Lasix) have a central role in the management of CHF to improve symptoms in patients with fluid retention. Fluid overload should be minimized so that other medications (such as ACE inhibitors and beta blockers) can work better. In patients with diastolic dysfunction(or Heart Failure with Preserved Ejection Fraction), excessive diuresis can worsen failure by decreasing left ventricular filling, so diuretics should be used with caution.
Certain Beta-blockers such as metoprolol succinate have a central role in the management of both diastolic and systolic heart failure. Specifically, bisoprolol, carvedilol, and sustained-release metoprolol have been shown to reduce mortality in patients with NYHA Class II and III systolic heart failure (Grade C failure). Physicians need to have caution when starting beta-blocker therapy, since their negative inotropic and chronotropic effects can worsen failure initially. Generally, they should not be started in the setting of decompensated failure, and should be titrated up to maximal doses very slowly.
Eplerenone was compared to placebo in a 2011 randomized, double-blind trial for NYHA Class II heart failure. Eplerenone reduced both the risk of death and the risk of hospitalization among patients with systolic heart failure whose ejection fraction was no more than 35% and who had mild symptoms (EMPHASIS-HF study).
Management of Diastolic Failure
The general principles of treatment are to minimize fluid overload with diuretics, control the blood pressure, slow down the heart rate (particularly in patients with atrial fibrillation), and manage comorbid CHD.
Many physicians start with either a beta-blocker or non-dihydropyridine calcium channel blocker (such as diltiazem) in order to slow down the heart rate, increase the ventricular filling time, and decrease the blood pressure.
Excessive diuresis and preload reduction can actually worsen diastolic failure.
Radiographic Findings of Congestive Heart Failure
Cardiomegaly: Defined when the width of the heart is more than half of the width of the thorax.
Central vascular congestion and hilar fullness: Patients in failure frequently have hilar fullness on a PA chest film. Individual vessels may appear enlarged.
Pleural effusions: Identified by a blunting of the costophrenic angles. This can be seen posteriorly on a lateral film as well. Occasionally, prominent fluid in the horizontal fissure will be seen in the right lung.
Cephalization of pulmonary vasculature: Typically, pulmonary vessels are not well seen in the upper lung fields. In CHF, however, they become engorged and can be seen extending from the hilum.
Kerley B lines: These are small linear densities 2-3 cm in length seen in the periphery of the lung fields on the PA view. They represent interstitial fluid in the lung tissue.
Echocardiogram
Two-dimensional echocardiography measures the size of the chambers, the thickness of the walls, and the size of the cavity.
It also evaluates the movement of heart structures.
Doppler assesses blood flow (direction and velocity) through the valves and chambers.
The ratio of left ventricular filling velocities (E/A ratio) is a marker of diastolic dysfunction. The E/A ratio is reduced when diastolic dysfunction is present.
Positive Stress Test Followup
A positive stress test does not confirm coronary artery disease and should be followed up with cardiac cath to identify and quantify the stenoses. These results will also be helpful in deciding whether the patient needs an angioplasty and stent or a coronary bypass.
Exercise treadmill testing (ETT)
The ACC/AHA 2002 Guideline Update for Exercise Testing makes the case that all patients with intermediate risk (i.e. between ~10 and 80% risk) should undergo exercise treadmill testing (ETT) as the initial diagnostic test for suspected CAD. A major exception to this rule is for patients in whom the baseline EKG is not interpretable (which includes those with Wolff- Parkinson-White syndrome, a paced heart rhythm, a left bundle branch block, or more than 1 mm of ST depression at baseline). The negative predictive value of a normal ETT in a patient with reasonably high risk is not very good. For example, in a patient with a 50% pre-test probability, a negative ETT would lead to a post-test probability of 30%, which is still too high to effectively rule out CAD. Furthermore, some have argued that ETTs are less predictive of CAD in women compared to men.
