UMEM Educational Pearls - Cardiology

 

There are several criteria used to diagnose LVH via ECG, none 100% accurate though by using multiple criteria sets, the sensitivity and specificity are increased
 
1.) Romhilt-Estes Criteria (diagnostic>5 points):
R or S limb leads ≥20 mm, or S in V1 or V2 ≥30 mm, or R in V5 or V6 ≥30 mm = 3pt
ST-T vector opposite to QRS without digitalis = 3pt
ST-T vector opposite to QRS with digitalis = 1pt
Negative terminal P mode in V1 1 mm in depth and 0.04 sec in duration = 3pt
Left axis deviation = 2pt
QRS duration ≥0.09 sec = 1pt
Delayed intrinsicoid deflection in V5 or V6 (>0.05 sec) = 1pt
 
2.) Cornell Criteria:
S in V3 + R in aVL > 28 mm (men)
S in V3 + R in aVL > 20 mm (women)
 
3.) Sokolow-Lyon Criteria:
S in V1 + R in V5 or V6 ≥ 35 mm 
R in aVL ≥ 11 mms

Show References



 

Acute coronary thrombotic occlusion is the most common trigger of cardiac arrest
The benefit of coronary angiography  seems to be well established in patients who regain consciousness soon after recovery of spontaneous circulation
Whether emergency coronary angiography and PCI improve survival in patients who remain unconscious after ROSC remains unknown
Results of this study can be summarized as follows:
       1. CAD and acute or recent culprit coronary lesions are present in most resuscitated unconscious  patients with OHCA without obvious extracardiac cause
       2. CAD and acute or recent culprit coronary lesions are observed in most patients with ST-segment elevation and in a non-negligible proportion of patients with other ECG patterns on post-ROSC electrocardiograph
       3. Emergency coronary angiography and successful emergency PCI are independently related to in-hospital survival after OHCA

Show References



 

  • HIV infected patients are at higher calculated risk for CHD compared w/the general population of the same age
  • HIV is known to promote atherosclerosis through mechanisms related to immune activation, chronic inflammation, coagulation disorders, and lipid disturbances
  • Additionally combination anti-retroviral therapy (cART) has an affect on lipid and glucose metabolism demonstrated both in vitro and in vivo 
  • The presence of an accelerated process of coronary atherosclerosis in this population is a major concern 
  • Practitioners should have a high index of suspicion when confronted by young HIV patients and further data/strategies to prevent early CHD in HIV-infected patients is warranted

Show References



 

  • International guidelines recommend early invasive strategy (<24hrs) for patients with NSTEMI w/high risk factors defined by a GRACE score >140
  • A recent meta-analysis based on 7 RCTs & 4 observational studies demonstrated an inconclusive survival benefit with an early invasive strategy 
  • Heterogeneity across multiple studies including timing of intervention, definition of MI, patients' risk profiles, major bleeding, and sample size make the interpretation of survival results difficult
  • Based on the most recent data the optimal timing of intervention remains unclear and a more definite RCT is warranted to guide clinical practice
 

Show References



  • Sports are associated w/an increased risk for sudden cardiac death (SCD) in athletes who are affected by cardiovascular conditions predisposing to ventricular arrhythmias (VA)
  • SCD has substantially decreased in Veneto Italy due to the introduction of a preparticipation screening program that identifies unrecognized cardiovascular conditions
  • This study included 145 athletes evaluated for VA using a screening protocol of ECG, exercise testing, echocardiography, holter monitoring, and cardiac MRI
  • ECG was normal in most athletes (>85%)
  • VA were detected prevalently during exercise testing 
  • Cardiac MRI detected right ventricular regional kinetic abnormalities (ARVD) in 9 of 30 athletes 
  • A total of 30% of these athletes had potentially dangerous VA
  • In asymptomatic athletes w/prevalently normal ECG, most VA's can be identified by adding an exercise test 

 

Show References



Title: Transcatheter Aortic-Valve Replacement (TAVR)

Category: Cardiology

Keywords: Transcatheter Aortic-Valve Replacement (TAVR) (PubMed Search)

Posted: 2/17/2013 by Semhar Tewelde, MD
Click here to contact Semhar Tewelde, MD

 

  • Symptomatic aortic stenosis if left untreated has a high mortality rate (5 yr mortality rate is 50% w/angina, 3 yr mortality rate is 50% w/syncope, and 2 yr mortaltiy rate is 50% w/CHF)
  • Standard tx includes medical therapy +/- balloon aortic valvuloplasty
  • A recent study comparing standard therapy to transcatheter aortic-valve replacement (TAVR) revealed rates of death at 2 yrs were 68% in standard therapy group vs. 43.3% in TAVR group (p<0.001)
  • At 2 yrs the rate of rehospitalization was 72.5% in standard therapy group vs. 35% in TAVR group
  • The rate of stroke was higher after TAVR vs. standard therapy in the 1st 30 days
  • In appropriate patients with severe AS who are not surgical candidates TAVR reduced rates of death, hospitalizations, and symptoms at 2 yr follow-up

 

Show References



-Common life-threatening cardiovascular effects of cocaine intoxication include tachydysrhythmias, ventricular fibrillation, myocardial ischemia, and infarction.

-Emergency management of acute cocaine intoxication relies mainly on supportive and symptomatic treatment, w/liberal use of gamma-aminobutyric acid receptor agonists such as benzodiazepines.

-Intravenous lipid emulsion (ILE) therapy has been used successfully to treat cardiac toxicity associated with a variety of lipid-soluble drugs, such as local anesthetics, calcium/beta-blockers, tricyclic anti-depressants, and cocaine. 

-The current hypothesis, called the “lipid sink” hypothesis, suggest that ILE infusion creates an expanded lipid phase in the plasma that absorbs the circulating lipophilic toxin and decreases the amount of free unbound toxin available to bind to the myocardium.

-When life-threatening cardiac arrhythmias (e.g. wide-complex tachycardia/prolonged QT) are not amenable to standard therapy (e.g. sodium bicarbonate/magnesium) consider ILE as a potential option to the current algorithm. 

Show References



Title: Chest compression only CPR

Category: Cardiology

Posted: 2/3/2013 by Semhar Tewelde, MD (Updated: 2/18/2025)
Click here to contact Semhar Tewelde, MD

  • Early CPR performed by laypersons can double the chances of survival in out-of-hospital cardiac arrest (OHCA)
  • A retrospective cohort that combined 2 RCT compared the survival effects of dispatcher CPR instruction consisting of chest compression alone or chest compression with rescue breathing
  • There was a lower risk of death after adjustment for confounders (adjusted hazard ratio 0.91, 95% confidence interval 0.83-0.99, p=0.02)
  • Findings strongly support a long-term mortality benefit of dispatcher CPR instruction strategy consisting of chest compression alone rather than chest compression plus rescue breathing

 

Show References



 

  • Many infants w/cyanotic heart disease only survive w/early surgical intervention
  • The most rapid & effective first-line therapy for stabilization of the crashing neonate is IV prostaglandin E1 (PGE1)
  • PGE1 serves to reopen the ductus arteriosus allowing partially desaturated systemic arterial blood to enter the pulmonary artery and be oxygenated
  • The widespread use of this agent has profoundly decreased morbidity & mortality 
  • The initial dose of PGE1 is 0.1 mg/kg/min
  • ADR for PGE1 include: apnea, hypotension, edema, and low grade fever

Show References



 

·       Cyanosis in the newborn is defined as an arterial saturation <90% and a PO2 <60 torr

·       To help differentiate between cardiogenic and non-cardiogenic causes initially obtain an arterial saturation on room air and obtain a subsequent measurements on 100% oxygen

·       Infants w/neurogenic or pulmonary causes of cyanosis will demonstrate increases in arterial blood saturation on 100% oxygen while infants with congenital heart disease show minimal elevation

·       There are 3 general sources of arterial desaturation in neonates with structural heart disease:

1.) Lesions with decreased pulmonary blood flow (tetralogy of Fallot, severe pulmonary stenosis/atresia, and tricuspid atresia)

2) Admixture lesions, in which desaturated systemic venous blood mixes with intracardiac blood, and then enters the aorta (transposition of great vessels, partial anomalous pulmonary venous drainage)

3) Lesions with increased pulmonary blood flow and pulmonary edema, in which diffusion barriers and intrapulmonary shunting prevent proper oxygenation (truncus arteriosus)

 

 

 

Show References



 

  • Ventricular assist devices (VAD) have become an option as bridge to transplant or destination therapy in many patients (prevalence heart failure in US 5.7 million)
  • VADs have significantly improved quality of life by NYHA class & 6 min walk distance 
  • 2 main types of VAD exist, pulsatile (PF) and continuous flow (CF), with 98% being CF
  • Both bleeding and thrombosis are frequently encountered complications
  • Although required systemic anticoagulation increases the risk of bleeding, there is a inherent association between CF VADs and GI AVMs
  • Hypotension a common complication, which should be assessed by ruling out: bleeding, thrombosis, mechanical obstruction, sepsis, and RV failure

Show References



Title: Blunt Cardiac Injury (BCI)

Category: Cardiology

Posted: 1/6/2013 by Semhar Tewelde, MD (Updated: 2/18/2025)
Click here to contact Semhar Tewelde, MD

 

  • BCI results in a spectrum of outcomes from asymptomatic to sudden cardiac death
  • Normal screening ECG is associated with a 98% negative predictive value 
  • Sinus tachycardia is the most common ECG abnormality among trauma victims
  • Myocardial contusion (MC) is the most common & ambiguous diagnosis following BCI
  • MC has no consensus definition or uniform diagnostic criteria and can be loosely defined as BCI w/mild increase in cardiac biomarkers or frank cardiac dysfunction (e.g. wall motion abnormalities, arrhythmias, conduction disturbances, or SCD)
  • BCI w/ a normal ECG & stable hemodynamics have a benign clinical course and rarely require further diagnostic testing or long periods of close observation
  • Individuals w/ECG abnormalities, hemodynamic instability, or rapid deceleration injury concerning for blunt aortic injury (BAI) warrant imaging of heart and great vessels by echocardiogram and CT scan 

Show References



 

  • Type 1: Ischemic myocardial necrosis secondary to plaque rupture (ACS)
  • Type 2: Ischemic myocardial necrosis not secondary to ACS, but rather supply/demand mismatch, vasospasm, emboli, anemia, hypoperfusion, and/or arrhythmia
  • Type 3: Sudden cardiac death
  • Type 4a: PCI related
  • Type 4b: Stent thrombosis
  • Type 5: CABG related 

Show References



 

  • ST-elevation may represent STEMI or other alternative diagnoses (e.g., aortic dissection)
  • Computed tomographic (CT) scanning may help in identifying these alternative diagnoses
  • ACTIVATE-SF Registry consists of patients w/a Dx of STEMI admitted to the ED 
  • 410 patients w/a suspected diagnosis of STEMI, 45 (11%) underwent CT scanning before primary PCI; 2 (4%) of these CT scans changed clinical management by identifying a stroke
  • Those who underwent CT scanning had far longer door-to-balloon times (median 166 vs 75 minutes, p <0.001) and higher in-hospital mortality (20% vs 7.8%, p=0.006)
  • CT scanning before PCI rarely changed management and was associated w/significant delays in door-to-balloon times

Show References



Title: Pulmonary Arterial Hypertension (PAH)

Category: Cardiology

Keywords: Pulmonary Arterial Hypertension (PAH) (PubMed Search)

Posted: 12/17/2012 by Semhar Tewelde, MD (Updated: 2/18/2025)
Click here to contact Semhar Tewelde, MD

 

  • PAH can be classified as primary (PPH) or secondary pulmonary hypertension (SPH)
  • Epoprostenol a prostacyclin analog was the first primary drug for patients w/PAH
  • Recent clinical trials describe combination therapy as superior in efficacy to traditional monotherapy
  • Varied etiologies of PAH hampers the performance of RCTs for each combination therapy
  • PAH is associated w/diminished endothelium factor & nitric oxide, increased phosphodiesterase enzyme leading to the development of the ET-1 receptor antagonist (ERA) bosentan and the PDE- V inhibitor sildenafil
  • RCTs are currently investigating the efficacy of three news agents in tx of PAH: imatinib, riociguat, and selexipag 

Show References



 

  • Coarctation of the aorta (CoA) is the 5th most common congenital heart defect.
  • CoA typically manifests as a discrete constriction of the aortic isthmus.
  • The majority of patients affected present in infancy with varying degrees of heart failure, which reflect predominantly the severity of the aortic narrowing. 
  • Some patients may not present until later in childhood or adolescence,  with upper extremity hypertension,  either due to less severe initial narrowing or to the development of collateral circulation bypassing the coarctation.
  • Tx options include surgery, balloon angioplasty, and stenting.
  • Although early surgery may prevent/delay the onset of hypertension, approximately 30% will be hypertensive by adolescence.
  • HTN is the single most important outcome variable in patients with CoA
  • HTN present in young children is often under-recognized or not treated aggressively enough, screening for cardiovascular & renovascular anomalies is essential  
  • Untreated CoA has significant early mortality, with mean age of death ~30-40

Show References



Title: Kawasaki Disease

Category: Cardiology

Keywords: Kawasaki Disease, Mucocutaneous lymph node syndrome (PubMed Search)

Posted: 12/2/2012 by Semhar Tewelde, MD (Updated: 2/18/2025)
Click here to contact Semhar Tewelde, MD

 

Kawasaki disease (KD) is the leading cause of acquired heart disease in North American & Japanese children
Children w/KD should undergo a 2-D echocardiogram and electrocardiogram
In the acute phase, the myocardium, pericardium, endocardium, valves, conduction system, and coronary arteries may all be involved
KD shock syndrome is a cardiovascular manifestation that presents with hypotension, LV systolic dysfunction, coronary artery aneurysm, and a shocklike state
AHA recommends KD tx w/a single dose of 2 g/kg of IVIG infused over 12 hours plus high-dose aspirin at a dose of 80 to 100 mg/kg per day in 4 divided doses
More than 50% of coronary artery aneurysms regress within the first 2 years of onset 
Regression is associated with marked thickening of the intima, which  may later stimulate atherosclerosis with a risk for ischemic heart disease

Show References



Title: Rheumatic Heart Disease

Category: Cardiology

Keywords: Rheumatic fever, rheumatic heart disease (PubMed Search)

Posted: 11/25/2012 by Semhar Tewelde, MD (Updated: 2/18/2025)
Click here to contact Semhar Tewelde, MD

 

Rheumatic heart disease (RHD) causes  ~250,000 premature deaths every year
Worldwide RHD is the leading cause of heart failure in children and young adults
RHD manifests as a combination of fever, polyarthritis, carditis, chorea, erythema marginatum, and subcutaneous nodules (major Jones Criteria)
Mitral valve incompetence is the most common valvular lesion and mitral stenosis usually develops later as a result of persistent or recurrent valvulitis with bicommissural fusion
Eradication of group A streptococcus with penicillin prevents the initial acute rheumatic attack
No treatment for RHD exists other than for its complications, including heart failure, atrial fib, ischemic embolic events, and infective endocarditis

Show References



Title: Long QT Syndrome Part II

Category: Cardiology

Keywords: Torsades de pointes, prolonged QT syndrome (PubMed Search)

Posted: 11/18/2012 by Semhar Tewelde, MD
Click here to contact Semhar Tewelde, MD

 

When polymorphic ventricular tachycardia (VT) is encountered the 1st step is to examine the QTc interval before/after the VT to see if it's prolonged
Torsades de pointes (TDP) typically begins with a premature ventricular depolarization, followed by a compensatory pause, and then a sinus beat with a markedly prolonged QT interval, subsequently followed by a train of polymorphic VT
The risk of developing TDP correlates with the degree of prolongation of QTc interval
Risk = 1.052x, where X is a 10-ms increase in QTc interval
Tx algorithm: ECG reveals prolonged QTc, review drug hx, discontinue all QT prolonging drugs, suppress early after depolarization (EAD) w/magnesium bolus & infusion, maintain serum K levels >4.5meq/L, consider isoproterenol infusion + cardiac pacing 

Show References



Bazett's Formula QTc = QT/RR1/2 

Show References