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When is Levosimendan used in CHF?

Levosimendan is available in Australia on a compassionate-use basis. It should be reserved for patients who do not respond to dobutamine or in those in whom dobutamine is contraindicated due to arrhythmia or myocardial ischaemia


What is the indication for biventricular pacing?

NYHA symptoms Class III/IV despite optimal medical therapy

dilated heart failure with an ejection fraction ≀ 35%

QRS duration ≄ 120 ms

sinus rhythm


What is the evidence behind biventricular pacing?

Significant mortality reduction

Symptom reduction

Reduced hospitalisation

Good in asymptomatic patients and in combo with ICD therapy in terms of death reduction and hospitalisation but not cost-effective at this point in time


What are the indications for ICD?

ICDs are first-line therapy for patients who have bee n resuscitated from ventricular fibrillation, or from sustained ventricular tachycardia with syncope, or from sustained ventricular tachycardia with haemodynamic compromise and an LVEF of ≀ 40%.


What is the evidence behind ICD therapy?

Use of ICDs is associated with a 20–30% relative reduction in mortality at 1 year, which is maintained over 3–5 years of follow-up. Long-term follow-up (mean of 5.6 years) of a subgroup of the ICDs study showed that survival curves continued to diverge. 

Absolute mortality of inpatients treated with amiodarone was 5.5% per year versus 2.8% per year in those receiving ICDs. 


When would you consider ICD plus CRT?

In patients in whom implantation of an ICD is planned to reduce the risk of sudden death, i t is reasonable to also consider CRT to reduce the risk of death and heart failure eve nts if the LVEF is ≀ 30% and the QRS duration is ≄ 150 ms (left bundle branch block morphology), with assoc iated mild symptoms (NYHA Class II) despite optimal medical therapy


What are the definite indicators for cardiac transplant?

Persistent NYHA Class IV symptoms

Volume of oxygen consumed per minute at maximal exercise (VO 2 max) < 10 mL/kg/min

Severe ischaemia not amenable to revascularisation

Recurrent uncontrollable ventricular arrhythmias


What drug changes can precipitate decompensated CHF?

- starting drugs that predispose to renal function and salt and water retention - ie NSAIDS, COX-2 inhibitors, steroids, thiazolidinediones

- negative inotropes i.e. diltiazem, verapamil, antiarrhythmics, high dose beta blockers


What comorbid conditions can precipitate decompensated heart failure?

Infections (particularly pulmonary) due to haemodynamic changes

Renal failure --> fluid overload

Anaemia or pulm emboli impairing oxygen delivery

Thyroid imbalance


What is the role of thiazide diuretics in decompensated CHF?

In a CHF patient, diuretic resistance happens due to homeostatic increase in distal tubular reabsorption of sodium.

In the short term, adding a thiazide can block sodium uptake in the distal tubule, evoking a powerful diuretic response.


What is the difference between APO and decompensated CHF?

APO is truly acute (hence the term ‘flash pulmonary oedema’) and is typically a condition of wet lungs without extravascular fluid overload (i.e. acute diastolic LV failure).

In decompensated CHF the picture is subacute, extending over more than 6 hours of increasing symptoms with clinical signs of intravascular, pulmonary and peripheral fluid overload


Which drug should you avoid in bilateral renal artery stenosis?



What is the role of nitrates in decompensated CHF?

Nitrates are predominantly venodilators, but also have the effect of epicardial artery dilatation, and hence they are particularly desirable in the setting of decompensation induced by cardiac ischaemia. Nitrates may also have a role in decompensation through their beneficial haemodynamic effects, particularly in reducing central blood volume and filling pressure (as occurs in APO treatment). This can often relieve symptoms of pulmonary congestion, particularly at night when the heart is exposed to increased filling pressures due to the recumbent position. Evidence from large-scale RCTs of the effect of nitrates alone in decompensated CHF is lacking.


In a patient with APO, what constitutes cardiogenic shock and what should you do?

The presence of hypotension (systolic blood pressure < 90 mmHg) with APO constitutes a diagnosis of cardiogenic shock and requires emergency circulatory assistance with inotropes and/or intra-aortic balloon pump insertion.


What are some causes of systolic, diastolic, and normal LV function CHF?

Systolic LV dysfunction—CHD, dilated cardiomyopathy, mitral regurgitation

Diastolic LV dysfunction—hypertensive heart disease, hypertrophic cardiomyopathy, aortic stenosis

Normal LV function—mitral stenosis


What is the hierarchy of emergency therapy of acute heart failure?


3 points about HFPSF (diastolic heart failure)

diagnosis of possible orprobable diastolic heart failure is based on the combination of clinical CHF and preserved LV systolic function.

-  symptoms and physical signs of CHF, chest radiological evidence and an LVEF of ≄ 45% on echocardiography, gated blood pool scanning, or direct left ventriculography

- NOT synonymous with diastolic dysfunction


What is the epidemiology of HFPSF?

- 30-50% of community patients with CHF have normal or near normal LV systolic function
- women and elderly
- largely hypertensive heart disease, age, and diabetes (after exclusion of coronary and valvular heart disease)
- high mortality rates, low short term mortality than systolic dysfunction


What investigations are done for diastolic heart failure and what are their findings?

 - restrictive or pseudonormal mitral inflow filling pattern
- LA enlargement
- reduced septal annular velocity

- elevated LVEDP
- Prolonged Tau


What are the diagnostic criteria for diastolic heart failure (HFPSF?)

- clinical hx of CHF
- exclude myocardial ischaemia, valvular disease
- objective evidence of CHF (i.e. CXR)
- EF >45% (echo, gated, left ventriculography)
- echo or cath evidence of diastolic dysfunction where possible
- NOT plasma BNP


Which is superior for patients with LV systolic CHF and drug resistant symptomatic AF - AV node ablation w/ bi-ventricular pacing or pulmonary vein isolation and ablation?

For patients with CHF due to LV systolic
dysfunction associated with drug-resistant symptomatic AF, the study demonstrated the superiority of a rhythm-control strategy based on pulmonary vein isolation compared with a ventricular rate-control strategy based on atrioventricular node ablation with biventricular pacing.


In CHF patients, what is the strongest single predictor of suddent cardiac death?



How is the CHF of severe aortic stenosis managed?

Poorly to medical therapy
Arterial vasodilators including ACEIs are contraindicated due to the risk of coronary hypoperfusion
Appropriate medical therapy = digoxin and diuretics


What is the management of angina in CHF?


Avoid nondihydropyridine CCBs in LVEFs <40%

Use betablockers wherever tolerated for angina

Prophylactic nitrates

Severe angina + systolic heart failure + inoperable disease - consider perhexiline (last line, highly toxic)


How should you treat decubitus angina? (nocturnal angina associated with orthopnoea)

Treat as CHF
Loop diuretic in the arvo to minimise filling pressures overnight and prophylactic night tiem nitrates


What is perhexiline?

Nonselective CCB
Last line for angina
CYP450 - watch out for liver toxicity


What is the role of ACEIs in protecting against CHF?

- after acute anterior infarction, ACEIs have been shown to protect against development of CHF independent of baseline renal function and preserve renal function

- in patients with type 2 DM and nephropathy, ARBs protect against the development of CHF


What is the role of spironolactone in CHF and renal failure?

Spironolactone carries a significant risk of hyperkalaemia, particularly in patients who are also taking an ACE I or an angiotensin II receptor antagonist and whose creati nine clearance is less than 30 mL/min. It should be used with caution in patients with creatinine clearances between 30–60 mL/min


What is the link between chemotherapy and CHF?

Cancer chemotherapy, particularly with anthracycline (the 'rubicins and mitoxantrone)derivatives, may lead to the development of CHF; the risk is directly related to cumulative anthracycline dosage. Pre- existent impairment of LV systolic function represents a relative contraindication to aggressive chemotherapy with such agents


What impact does diabetes have on CHF?

The diagnosis of diabetes is not only an independent risk factor for the development of CHF, but is also associated with an adverse outcome in patients with established disease.