Cardiovascular emergencies in dialysis patients

Professor. Salwa Ibrahim, MD MRCP (UK)Cairo University

Agenda

• Spectrum of CV emergencies in dialysis patients

• Management

Acute Pericarditis

Uremic pericarditis

• Pericarditis either before or within 8 weeks of initiating renal replacement therapy

Pathophysiology

• Pericarditis arises from accumulation of biochemical irritants

• Calcium alterations, high PTH, and uremic toxins have been blamed

Dialysis Related Pericarditis

• Pericarditis after 8 weeks of renal replacement therapy

May be secondary to Inadequate dialysisVolume overloadHypercatabolic conditions Hyperparathyroidism Infection (especially viral)

•

Clinical Presentation

• Chest Pain (41-100%)

• Cough or dyspnea (31-57%)

• Malaise (54-66%) • Weight Loss (40%) • Fever (75-100%)

Diagnosis

• ECG does not show typical ST segment and T wave changes

• Echo is used to assess the size of the effusion

Treatment

• Uremic Pericarditis

• Intensive HD or PD causes rapid improvement

• Systemic anticoagulation should be avoided because of the high risk of hemorrhage

Dialysis Related Pericardial Effusion

• Large (>250cc pericardial effusion, posterior echo free space more than 1cm)

– Drainage

• If hemodynamically unstable needs drainage

• Medium and Small Effusions– Intensive Dialysis (5-7/week)– Serial monitoring by

echocardiography

Ischemic Heart Disease

Risk factors of IHD in dialysis

Traditional risk factors• Age• Male gender• Smoking• Family history• Hypertension• Diabetes mellitus• LVH

Risk factors unique for dialysis• Anemia• Hyperpathyroidism• Uremia• Hyperphosphatemia• Malnutrition• Volume overload• AVF

K/DOQI

• The K/DOQI guidelines recommend to screen ESRD for CVD at the start of dialysis

1. ECG2. Echocardiography3. Coronary artery calcium scoring for selected cases4. Coronary angiography for revascularization candidates

How to manage Angina during dialysis session

History, physical examination, ECG and cardiac enzyme evaluation should be performed.

If dialysis is continued, the administration of oxygen and aspirin, reduction of the desired ultrafiltration and/or blood pump speed, and administration of nitrates or morphine

Prevention

• Anemia management (Hb level 10.5-12.5g/dl)

• Careful PRBCs transfusion if target not met

• Gentle HD to avoid hypotension

Angina during dialysis may be prevented with the administration of nitrates and/or beta blockers prior to the treatment.

The efficacy of these agents is diminished since they commonly result in hypotension, thereby reducing the ability to effectively remove extracellular fluid.

2013 Kidney Disease Global Outcomes (KDIGO) organization clinical practice guideline in on lipid management and

treatment

Acute Myocardial Infarction

• Acute MI is common among ESRD with poor outcome

• Atherosclerosis/arteriolosclerosis contribute to LVH and increased myocardial oxygen demands and reduced coronary perfusion

• Cardiac troponin is misleading in dialysis cases

• Cardiac troponin I is more sensitive than cardiac troponin T or CK-MB

Management

• Prevention : ASA/ clopidogrel, BB, ACEI and nitrates

• Thrombolytics and glycoprotein IIb/IIIa antagonists are beneficial as in general population

• LMWH is superior to UFH but likely to be associated with bleeding

Revascularization

• CABG and angioplasty/ stenting should be considered in urgent cases as in general

Sudden death

Ritz, E. et al. J Am Soc Nephrol 2008;19:1065-1070

Causes of death in the 4D (Die Deutsche Diabetes Dialyse) study

Epidemiology of sudden death in Dialysis

• In the United States Renal Data System database 62% of

cardiac deaths (or 27% of all deaths) are attributable to arrhythmic mechanisms.

• Ventricular fibrillation/tachycardia were the predominant rhythm disturbance

Sudden Death

• Two peaks

First few hours after the first HD of the week( rapid electrolyrte shifts)

Before the first HD of the week end of the long interval- (hyperkalemia)- dead in bed syndrome

Bleyer AJ et al: KI ( 2006) 69: 2268-2273

Risk factors for sudden death in dialysis patients

LVH and heart failure

Coronary artery calcification

Abnormal myocardial structure and function fibrosis, microvessel disease

Electrolyte shifts and hypervolemia (related to dialysis sessions)

Hyperphosphatemia

QT prolonging medication

Sympathetic overactivity and autonomic nerve dysfunction

Low dialysate potassium is associated with the risk of sudden death

Low vitamin D is associated with the risk of SD

Management of cardiac arrest during dialysis

• Check responsiveness• Open airway• Check breathing• Give 2 effectives breaths• Check circulation• Precordial thump• Start CPR• Attach defibrillator

Prevention of sudden death in dialysis

Prevention of sudden death

• Routine very low potassium dialysate should be avoided• beta-blockers and (ACEIs) are proven therapies for reducing

mortality in patients with congestive heart failure. • A small prospective randomized trial of carvedilol in 114

dialysis patients with dilated cardiomyopathy. • They found a significant reduction in CVS mortality and a

trend toward reduction in sudden death• The largest prospective trial of ACEIs in dialysis patients, found

no reduction in CVS events for fosinopril compared to placebo in prevention of sudden death

Implantable cardioverter defibrillators (ICDs)

• Observational data suggest that for cardiac arrest survivors on dialysis, the benefit of ICD implantation is not attenuated by ESRD.

• A 42% reduction in all-cause mortality for patients receiving ICDs, even after adjustment for comorbid illness.

• The role of ICDs for primary prevention of sudden cardiac death in dialysis patients remains uncertain.

Arrhythmia

Cardiac Arrhythmias

• Acute : Ventricular Tachycardia Ventricular Fibrillation

Acute Arrhythmias

• Dialysis session should be terminated

• Urgent Cardioversion as per ACLS Guidelines

• Amiodarone –1stline drug: Ventricular Tachycardia

Intradialytic Hypotension

Definition

• IDH is defined as a decrease in SBP by ≥20 mm Hg associated with symptoms that include: nausea; vomiting; restlessness; dizziness; and anxiety.

• It can induce cardiac arrhythmias, predisposes to coronary and/or cerebral ischemic events.

Higher UF rates are associated with greater CV mortality

Etiology

• Age, anemia• Female Gender • Presence of diabetes mellitus• Hyperphosphataemia• Presence of coronary artery disease • Use of nitrates/antihypertensives• Autonomic neuropathy• Warm dialysate/acetate buffer• Eating during sessions• Pericardial effusion• Septicemia• Occult bleeding• arrhythmia

Pathophysiology

• Interplay of four factors

1. Ultra-filtration

2. Refill blood volume

3. Dialysate (Na+, Ca++, Temp)

4. Patient sensitivity to volume withdrawn

Prevention

• Dry Weight Assessment

• Clinical assessment , IVC diameter

• BNP level

• Echocardiography, ECG

Prevention

• Intradialytic Blood Volume monitoring

• Slow longer dialysis

• Sequential UF/dialysis

• Na+ > or equal 144mEq

• Bicarbonate dialysate

• Low temperature (36.5-35)

• High dialysate calcium

Blood Volume Monitoring

Measures hematocrit in arterial blood

Crit-Line® Technology

Blood volume change – surrogate marker for vascular refilling

Increase in hematocrit relative to decrease in fluid removal

The Inverse Relationship between blood volume and hematocrit

0 1 2 3 4

0

-5

-10

-15

-20

27

29

31

33

35

%B

V (

Lo

ss)

Hc

t

Hct =RCVBV

X 100

Not reliable in clinical studies

Treatment of IDH

• Place patient head down

• 100 cc bolus NS

• Reduce UF to zero

• Midodrine in refractory cases

• 6-week Sertraline therapy (SSRI)

Air embolism

Air embolism

Fatal cause of chest pain and dyspnea during dialysis.

Disconnection of connecting caps and/or blood lines can lead to air embolism in patients being dialyzed with central venous catheters.

Foam in the venous blood line should raise the suspicion that air is entering the dialysis system.

Clinical manifestations

Symptoms of the air embolism depend upon the patient's position

In the seated patient, air tends to migrate into the cerebral venous system without entering the heart leading to loss of consciousness and seizure

Those who are recumbent, air tends to enter the heart and then the lungs leading to dyspnea, cough, chest pain

Management

• Clamp the venous blood line

• Stop the blood pump

• Put the patient in the recumbent position on the left side with the chest and head titled downwards

• Cardiorespiratory support

• Supplemental Oxygen

• Aspiration of air from the atrium/ventricle

Infective endocarditis

Clinical Presentation

• Complication of catheter related bacteremia

• MV/AV affection is common because of calcification

• Fever, leucocytosis, new murmur

Management

• Blood cultures/THE/TEE

• Empirical therapy with vancomycin+aminoglycosides

• Valve replacement (valve destruction, recurrent embolization, failure to respond)