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American Journal of Emergency Medicine 37 (2019) 80–84

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American Journal of Emergency Medicine

journal homepage: www.elsevier.com/locate/ajem

Original Contribution vs. in the acute management of atrial fibrillation in patients with failure with reduced ejection fraction☆,☆☆

RaeAnn Hirschy, PharmD a,⁎, Kimberly A. Ackerbauer, PharmD b,GaryD.Peksa,PharmDc, E. Paul O'Donnell, PharmD c,d,JoshuaM.DeMott,PharmD,MScc a Loyola University Medical Center, Maywood, IL 60153, United States b Boston Medical Center, Boston, MA 02118, United States c Rush University Medical Center, Chicago, IL 60612, United States d Midwestern University, College of Pharmacy, Downers Grove, IL 60515, United States article info abstract

Article history: Objective: The objective of this study was to examine the effects of metoprolol versus diltiazem in the acute Received 11 February 2018 management of atrial fibrillation (AF) with rapid ventricular response (RVR) in patients with with Received in revised form 29 March 2018 reduced ejection fraction (HFrEF). Accepted 27 April 2018 Methods: This retrospective cohort study of patients with HFrEF in AF with RVR receiving either intravenous push (IVP) doses of metoprolol or diltiazem was conducted between January 2012 and September 2016. The Keywords: fi fi primary outcome was successful rate control within 30 min of administration, de ned as a heart Atrial brillation b ≥ Heart failure rate (HR) 100 beats per minute or a HR reduction 20%. Secondary outcomes included rate control at 60 min, maximum median change in HR, and incidence of , , or conversion to normal sinus rhythm Metoprolol within 30 min. Signs of worsening heart failure were also evaluated. Diltiazem Results: Of the 48 patients included, 14 received metoprolol and 34 received diltiazem. The primary outcome, successful rate control within 30 min, occurred in 62% of the metoprolol group and 50% of the diltiazem group (p = 0.49). There was no difference in HR control at predefined time points or incidence of hypotension, bradycardia, or conversion. Although baseline HR varied between groups, maximum median change in HR did not differ. Signs of worsening heart failure were similar between groups. Conclusions: For the acute management of AF with RVR in patients with HFrEF, IVP diltiazem achieved similar rate control with no increase in adverse events when compared to IVP metoprolol. © 2018 Elsevier Inc. All rights reserved.

1. Introduction Heart Rhythm Society Guideline for the Management of Patients With recommends intravenous non-dihydropyridine Atrial fibrillation (AF) and heart failure (HF) are frequently encoun- channel blockers or beta-blockers for acute HR control in tered in the acute setting. Both AF and HF affect millions of people in the hemodynamically stable patients presenting with AF without HF [3]. United States and share several common risk factors, including age, hy- The aforementioned guideline and the 2013 American College of pertension, diabetes mellitus, ischemic heart disease, and valvular heart Cardiology Foundation and American Heart Association Guideline for disease [1]. Of those with AF, 73% of men and 76% of women develop HF, the Management of Heart Failure recommend against the use of non- and of patients with HF, 62% of men and 73% of women develop AF [2]. dihydropyridine blockers and permit the use of beta- Atrial fibrillation with rapid ventricular response (RVR) is frequently blockers in patients with HF with reduced ejection fraction (HFrEF); defined as (HR) ≥ 120 beats per minute (bpm). The 2014 however, both non-dihydropyridine calcium channel blockers and American Heart Association, American College of Cardiology, and beta-blockers have negative inotropic effects which can be harmful during an acute HF exacerbation [3,4]. Available literature on non- dihydropyridine calcium channel blockers in patients with HFrEF ☆ Sources of support: None. focus on chronic management in which patients are exposed to the ☆☆ Conflict of interest: No listed authors have any conflict of interest to the subject mat- long-term negative inotropic effect without the neurohormonal bene- ter in this manuscript. fits that beta-blockers provide [3-6]. Furthermore, studies comparing ⁎ Corresponding author at: Clinical Pharmacy Specialist, Critical Care, Loyola University Medical Center, 2160 S 1st Ave, Maywood, IL 60153, United States. the use of non-dihydropyridine calcium channel blockers and beta- E-mail address: [email protected] (R. Hirschy). blockers in the acute management of AF with RVR often exclude

https://doi.org/10.1016/j.ajem.2018.04.062 0735-6757/© 2018 Elsevier Inc. All rights reserved. R. Hirschy et al. / American Journal of Emergency Medicine 37 (2019) 80–84 81 patients with severe, New York Heart Association (NYHA) Class IV, or support, new pulmonary edema, or increased oxygen requirement decompensated HF, and fail to acknowledge use in compensated within 48 h or readmission within 7 days of discharge were also evalu- HFrEF [7-9]. ated [13-15]. The short-term use of diltiazem for the acute management of AF with RVR in patients with HFrEF has not been fully evaluated. Therefore, 2.5. Analysis the primary objective of this study was to compare the achievement of a goal HR of b100 bpm or a HR reduction of at least 20% in patients with Analyses were performed on Statistical Package for the Social HFrEF receiving intravenous push (IVP) metoprolol versus IVP diltiazem Sciences (SPSS, Inc., Armonk, NY), version 23.0. Continuous data were for rate control of AF with RVR in the emergency department (ED). reported as median and interquartile range [IQR] and categorical data as frequencies and percentages. The Mann Whitney U test was utilized 2. Methods for continuous data and Pearson chi-square or Fisher's exact test was used, as appropriate, for categorical data. An a priori significance level 2.1. Study design was set as p b 0.05.

This was a single-center, retrospective cohort study from January 3. Results 2010 through September 2016 of patients with a diagnosis of AF (International Statistical Classification of Diseases and Related Health Of 551 screened patients, 48 patients were included, 14 received Problems-9/10 (ICD-9/10)) treated with IVP metoprolol or IVP metoprolol and 34 received diltiazem. The most common reasons for diltiazem in the ED. The study site was a tertiary medical center ED exclusion were an EF N 40% (n = 272) and presentation with a rhythm with approximately 50,000 to 70,000 patient visits per year during other than AF with RVR (n = 114, Fig. 1). All baseline characteristics the study period. The study was registered in ClinicalTrials.gov were similar between groups except baseline HR (metoprolol 129 (NCT02938260) and approved by the local Institutional Review Board. [124–145] bpm versus diltiazem 141 [130–158] bpm; p =0.02),outpa- The study population was a sample size of convenience. tient beta-blocker use (metoprolol group 100% versus diltiazem group 68%; p = 0.02), and past medical history of coronary disease 2.2. Patients (metoprolol 71% versus diltiazem 38%; p = 0.04). Of note, there was no baseline difference in the median Rapid Emergency Medicine Score Included patients were ≥18 years of age, treated for AF with RVR, and (metoprolol 8 [4–9] versus diltiazem 8 [4–9]; p =0.47;Table 1). had a documented EF ≤ 40%. Rapid ventricular response was defined as The primary outcome, successful rate control within 30 min, HR ≥ 120 bpm and EF was confirmed via an echocardiogram within the occurred in 8 of 13 patients (62%) in the metoprolol group and 15 of previous five years from the index visit. Patients could receive one 30 patients (50%) in the diltiazem group (p = 0.49). The primary additional IVP dose within 30 min after the first dose, but were excluded outcome was not assessed for 5 patients (1 in the metoprolol group if crossover occurred between treatment . Other exclusion and 4 in the diltiazem group) due to documentation omissions within criteria were pregnancy, pre-treatment systolic pressure (SBP) the electronic medical record. No difference was found for incidence b 90 mm Hg, or decompensated HF. Decompensated HF was defined of hypotension, bradycardia, or conversion to normal sinus rhythm at as presentation with signs and symptoms of worsening HF. 30 min. There was also no difference between groups with respect to successful rate control or heart rate at the pre-specified time points of 2.3. Methods and measurements 60 min and transfer to an inpatient unit. The maximum median change in HR was 30 [10–52] bpm in the metoprolol group versus 32 [18–47] Patients were grouped by medication: metoprolol or diltiazem. bpm in the diltiazem group (p = 0.60; Table 2). Heart rate at various Study data were collected and managed using REDCap electronic data time points is illustrated in Fig. 2. capture tools hosted at Rush University Medical Center [10]. Electronic No difference was found between groups for any signs of worsening medical records were used to obtain clinical and demographic data, in- HF. All patients were admitted to the hospital. There was no difference cluding age, sex, race, SBP (baseline and 30 min), EF, NYHA Class, home in admission to the intensive care unit versus medical ward. No differ- medications, past medical history, diastolic BP (baseline), HR (baseline, ence was found between groups in rates of readmission within 7 days 30 min, 60 min, and at transfer to an inpatient unit), respiratory rate, (metoprolol 7% versus diltiazem 12%; p = 1.00). For all patients with re- Glasgow Coma Scale, oxygen requirement (baseline and increase within admission within 7 days, discharge diagnoses were evaluated and none 48 h), oxygen saturation, dose and frequency of study medications, contained a diagnosis of worsening HF (Table 2). other medications administered in the ED, inotropic support, pulmo- While in the ED, patients frequently received 5 mg of metoprolol and nary edema, and readmission within 7 days. These values contributed 15 mg of diltiazem (15 [10−20]) for the first dose. A second dose was to the calculation of a Rapid Emergency Medicine Score (REMS), administered in 21% of the patients in each group. The second doses which is an externally validated tool for in-hospital mortality estimates were consistently 5 mg of metoprolol and 10 mg of diltiazem within in nonsurgical patients presenting to the ED [11]. The administration 30 min with a median time between doses of 23 min [13−23] in the time of the first IVP dose of metoprolol or diltiazem was utilized as metoprolol group and 16 min [8–30] in the diltiazem group (p =1.00; time zero and other time points are based off of this. Table 3). Concomitant medication administration varied with usage of oral beta-blockers (metoprolol group 43% versus diltiazem group 0%: 2.4. Outcomes p b 0.01) and continuous infusions of diltiazem (metoprolol 0% versus diltiazem 44%: p b 0.01). Use of IV in the ED to control The primary outcome was successful rate control (HR b 100 bpm or symptoms of HF was also examined and did not vary between groups a HR reduction ≥ 20%) within 30 min from administration of the first (Table 3). dose of IVP metoprolol or IVP diltiazem [7,12]. Secondary outcomes consisted of HR (30 min, 60 min, and at transfer to an inpatient 4. Discussion unit), successful rate control (60 min and at transfer to an inpatient unit) and incidence of hypotension (SBP b 90 mm Hg), bradycardia We evaluated the acute management of AF with RVR in patients (HR b 60 bpm), and conversion to normal sinus rhythm within 30 min. with HFrEF presenting to the ED. The achievement of successful rate Maximum median change in heart rate and hospital admission unit control (HR b 100 bpm or a HR reduction ≥ 20%) in patients receiving were collected. Worsening HF symptoms, defined as new inotropic IVP metoprolol versus IVP diltiazem did not differ between groups at 82 R. Hirschy et al. / American Journal of Emergency Medicine 37 (2019) 80–84

Screened for Inclusion n = 551

Excluded Patients n = 503 Normal ejection fraction (>40%) (n = 272, 54%) Heart rhythm other than AF with RVR (n = 114, 23%) Multiple admissions within timeframe (n = 51, 10%) Heart failure exacerbation (n = 43, 9%) Received non-study medication (n = 15, 3%) Lack of monitoring in timeframe (n = 7, 1%) Systolic <90 mmHg (n = 1, <1%)

Total Included n = 48

Metoprolol Diltiazem n = 14 n = 34

Fig. 1. Patient enrollment flow chart.

30 min, 60 min, or at transfer to an inpatient unit. A difference existed Table 1 Baseline characteristics.a in baseline HR between groups; however, both groups had similar maximum median changes in HR following treatment. Overall, no Characteristic Metoprolol Diltiazem p-Value difference was noted between groups with regards to HF symptoms. (n = 14) (n = 34) To date, this is the only study to analyze the use of IVP metoprolol versus Age 69 [51–76] 67 [56–80] 0.65 IVP diltiazem for the acute management of AF with RVR, specifically in Female 5 (36) 12 (35) 1.00 patients with non-decompensated HFrEF. Race Caucasian 6 (43) 9 (26) 0.32 In a recent study, Fromm et al. investigated IV metoprolol versus IV African American 6 (43) 20 (59) 0.31 diltiazem for HR control in patients with AF with RVR and reported suc- Hispanic 2 (14) 4 (12) 1.00 cess (HR of b100 bpm within 30 min) in 46.4% of patients receiving IV Asian 0 (0) 1 (3) 1.00 metoprolol and 95.8% of patients receiving IV diltiazem (p b 0.0001) Systolic blood pressure (mm Hg) 137 [111–154] 134 [111–155] 0.91 Heart rate (bpm) 129 [124–145] 141 [130–158] 0.02 [8]. However, this study and others evaluating metoprolol and diltia- Ejection fraction (%) 23 [15–35] 25 [15–30] 0.96 zem, excluded patients with Class IV HF and acute decompensated HF New York Heart Association Class [7-9]. Scheuermeyer et al. reported the frequency of heart failure in I 6 (43) 15 (44) 0.94 their population (9.0% in the calcium group and 8.8% II 3 (21) 7 (21) 1.00 in the group); however, the study did not differentiate be- III 4 (29) 12 (35) 0.75 IV 1 (7) 0 (0) 0.29 tween patients with HF when looking at response rates [9]. In contrast, Home medications HFrEF was necessary for inclusion into our study. ACE-inhibitorb 9 (64) 15 (44) 0.20 Available literature for the treatment of AF with RVR, specifically in Angiotensin blocker 0 (0) 8 (24) 0.09 patients with HF, is sparse. A study comparing diltiazem to placebo in Beta-blocker 14 (100) 23 (68) 0.02 Calcium channel blocker 2 (14) 9 (26) 0.47 patients with AF with RVR and severe HF found that 97% of those treated 4 (29) 2 (6) 0.05 with IV diltiazem had a reduction in HR of N20% and no symptoms of HF 0 (0) 1 (3) 1.00 exacerbation [12]. A second study of patients with decompensated HF 0 (0) 0 (0) 1.00 compared the use of IV metoprolol and IV diltiazem for control of AF Loop 6 (43) 11 (32) 0.52 with RVR. Both agents were equally effective at controlling HR with Home loop diuretic dose (mg)c 80 [35–140] 40 [20–80] 0.30 Past medical history no difference in reports of worsening HF or adverse events [15]. Atrial fibrillation 11 (79) 20 (59) 0.32 Current literature focuses on the risks associated with non- Asthma 2 (14) 4 (12) 1.00 dihydropyridine calcium channel blockers and patients with HFrEF, d COPD 2 (14) 4 (12) 1.00 but these effects are with long-term treatment [3-5]. The most refer- 10 (71) 13 (38) 0.04 fi Rapid Emergency Medicine Score 8 [4–9] 8 [4–9] 0.47 enced study reports an increase in rst recurrent cardiac event (cardiac death or nonfatal re-infarction) in patients on diltiazem over placebo. a All values reported as median [IQR] or n (%). These patients were on therapy for 12 to 52 months, with a mean b Angiotensin-converting enzyme. c Reported dose in equivalent. duration of 25 months [6]. Prior studies, as well as this study; indicate d Chronic obstructive pulmonary disease. diltiazem is safe in the acute setting [12,16-18]. Both metoprolol and R. Hirschy et al. / American Journal of Emergency Medicine 37 (2019) 80–84 83

Table 2 Outcomes.a

Characteristic Metoprolol Diltiazem p-Value Odds ratio (95% CI) (n = 14) (n = 34)

30 min Successful rate controlb 8/13 (62) 15/30 (50) 0.49 0.63 (0.17–2.36) Heart rate (bpm) 114 [96–124] 110 [100−123] 0.87 – Hypotension 0 (0) 1 (3) 1.00 – Bradycardia 0 (0) 0 (0) 1.00 – Conversion 0 (0) 2 (6) 1.00 – 60 min Successful rate control 9 (64) 16 (47) 0.28 0.49 (0.14–1.78) Heart rate (bpm) 110 [94–118] 109 [99–120] 0.68 – Transfer to an inpatient unit Successful rate control 9 (64) 21 (62) 0.87 0.90 (0.25–3.27) Heart rate (bpm) 111 [97–126] 103 [92–114] 0.79 Maximum change in heart rate (bpm) 30 [10–52] 32 [18–47] 0.60 ICUc admission 10 (71) 30 (88) 0.21 3.00 (0.63–14.27) Inotrope within 48 h 0 (0) 1 (3) 1.00 – Increased pulmonary edema within 48 h 0 (0) 0 (0) 1.00 –

Increased O2 requirement within 48 h 3 (21) 11 (32) 0.51 1.75 (0.41–7.59) Readmission within 7 days 1 (7) 4 (12) 1.00 1.73 (0.18–17.05)

a All values reported as median [IQR] or n (%). b The primary outcome was not assessed for all patients due to a lack of documented vitals within 30 min. c Intensive care unit. diltiazem act as negative acutely but beta-blockers provide or inaccurate. There was no formal treatment protocol; therefore, long term neurohormonal benefits [19]. Our findings contradict the medication selection, dose, and timing of administration were based current Heart Failure and Atrial Fibrillation Guidelines on the avoidance on provider preference and nursing monitoring. The study was con- of non-dihydropyridine calcium channel blockers in all patients with ducted at a single tertiary medical center, limiting external validity. HF, specifically in the acute management of those in AF with RVR The sample size was small due to the specificity of this cohort, which [3,4]. In this study, no patients were re-admitted within 7 days of dis- may contribute to our inability to detect a difference. Dosing was fre- charge due to HF exacerbations after the short-term use of diltiazem quently ordered as a flat dose rather than a weight-based dose, although for the treatment of AF with RVR. prior evidence suggests greater success with weight-based dosing [7,8]. This study has several limitations. The retrospective design relied Also, despite the lack of a protocol the providers often order set doses on medical record documentation, which may have been incomplete of the study medications. Groups also differed in history of atrial

Fig. 2. Heart rate: baseline, 30 and 60 min post-medication administration, and prior to transfer to an inpatient unit. 84 R. Hirschy et al. / American Journal of Emergency Medicine 37 (2019) 80–84

Table 3 References Management in the emergency department.a [1] Lubitz SA, Benjamin EJ, Ellinor PT. Atrial fibrillation in congestive heart failure. Heart Characteristic Metoprolol Diltiazem p-Value Fail Clin 2010;6(2):187–200. https://doi.org/10.1016/j.hfc.2009.11.001. (n = 14) (n = 34) [2] Anter E, Jessup M, Callans DJ. Atrial fibrillation and heart failure: treatment consid- erations for a dual epidemic. Circulation 2009;119(18):2516–25. https://doi.org/ Dose 1 10.1161/CIRCULATIONAHA.108.821306. Actual dose (mg) 5 [5–5] 15 [10–20] [3] Yancy CW, Jessup M, Bozkurt B, et al. 2013 ACCF/AHA guideline for the management – – Weight based (mg/kg) 0.06 [0.04 0.08] 0.17 [0.13 0.23] of heart failure: a report of the American College of Cardiology Foundation/American Dose 2 Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol 2013;62(16): Administration of a second dose 3 (21) 7 (21) 1.00 e147-239. https://doi.org/10.1016/j.jacc.2013.05.019. 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The effect of diltiazem on mortality and Diltiazem infusion 0 (0) 15 (44) b0.01 reinfarction after myocardial infarction. N Engl J Med 1988;319(7):385–92. infusion 1 (7) 1 (3) 0.50 https://doi.org/10.1056/NEJM198808183190701. Repeat IVP 6 (43) 9 (26) 0.32 [7] Demircan C, Cikriklar HI, Engindeniz Z, et al. Comparison of the effectiveness of in- Opposite IVP 1 (7) 1 (3) 0.50 travenous diltiazem and metoprolol in the management of rapid ventricular rate IV diuretics in ED 1 (7) 4 (12) 1.00 in atrial fibrillation. Emerg Med J 2005;22(6):411–4 doi:22/6/411 [pii]. c Dose 40 30 [20–70] 0.80 [8] Fromm C, Suau SJ, Cohen V, et al. Diltiazem vs. metoprolol in the management of atrial fibrillation or flutter with rapid ventricular rate in the emergency department. a All values reported as median [IQR] or n (%). J Emerg Med 2015;49(2):175–82. https://doi.org/10.1016/j.jemermed.2015.01.014. b All patients received metoprolol 5 mg IVP and diltiazem 10 mg IVP for dose 2 so no [9] Scheuermeyer FX, Grafstein E, Stenstrom R, et al. Safety and efficiency of calcium IQR is reported. channel blockers versus beta-blockers for rate control in patients with atrial fibrilla- c Reported dose in furosemide equivalent. tion and no acute underlying medical illness. Acad Emerg Med 2013;20(3):222–30. https://doi.org/10.1111/acem.12091. [10] Harris PA, Taylor R, Thielke R, Payne J, Gonzalez N, Conde JG. Research electronic data capture (REDCap)—a metadata-driven methodology and workflow process fibrillation, home loop diuretic dose, and several home medications but for providing translational research informatics support. J Biomed Inf 2009;42(2): these did not reach significance. Differences in home medications and 377–81. [11] Olsson T, Lind L. Comparison of the rapid emergency medicine score and APACHE II past medical history could attribute to unequal groups at baseline or in nonsurgical emergency department patients. Acad Emerg Med 2003;10(10): be a sign of selection bias. While there was no difference between 1040–8. https://doi.org/10.1197/S1069-6563(03)00342-7. groups in ICU admission, it is important to note that these rates are [12] Goldenberg IF, Lewis WR, Dias VC, Heywood JT, Pedersen WR. Intravenous diltiazem fi fl fl for the treatment of patients with atrial brillation or utter and moderate to severe high because of the absence of a step-down cardiology oor at the congestive heart failure. Am J Cardiol 1994;74(9):884–9 doi:0002-9149(94)90580- study institution. Therefore, ICU admission should not be used as a sur- 0[pii]. rogate for severity of illness in our study, and we provided the Rapid [13] Kelly JP, Cooper LB, Gallup D, et al. Implications of using different definitions on out- comes in worsening heart failure. Circ Fail 2016;9(8). https://doi.org/10.1161/ Emergency Medicine Score for each group. CIRCHEARTFAILURE.116.003048. Future directions given the results of this study would be to conduct [14] Butler J, Gheorghiade M, Kelkar A, et al. In-hospital worsening heart failure. Eur J a prospective trial in this specific population to validate these results. It Heart Fail 2015;17(11):1104–13. https://doi.org/10.1002/ejhf.333. fi is still unclear if metoprolol or diltiazem is more effective in AF with RVR [15] Khatchi F, Nagaband S, Shuster J, Novak E, Joseph S. Treating rapid atrial brillation in acute decompensated heart failure: metoprolol and diltiazem are equally safe, yet due to conflicting results. Flat doses versus weight-based and maximum metoprolol increases conversion to sinus rhythm. J Card Fail 2014;20(8):S41. doses should be further assessed, as well. Prospective validation of the [16] Kulick DL, McIntosh N, Campese VM, et al. Central and renal hemodynamic effects safety of diltiazem in the acute setting with this patient population is and hormonal response to diltiazem in severe congestive heart failure. Am J Cardiol 1987;59(12):1138–43 doi:0002-9149(87)90862-9 [pii]. warranted. [17] Walsh RW, Porter CB, Starling MR, O'Rourke RA. Beneficial hemodynamic effects of intravenous and oral diltiazem in severe congestive heart failure. J Am Coll Cardiol 5. Conclusion 1984;3(4):1044–50. [18] Materne P, Legrand V, Vandormael M, Collignon P, Kulbertus HE. Hemodynamic ef- fects of intravenous diltiazem with impaired left ventricular function. Am J Cardiol In conclusion, for the acute management of AF with RVR in 1984;54(7):733–7 doi:S0002-9149(84)80199-X [pii]. patients with HFrEF, IVP diltiazem achieved similar rate control at [19] Bhatt AS, DeVore AD, DeWald TA, Swedberg K, Mentz RJ. Achieving a maximally tolerated β-blocker dose in heart failure patients: is there room for improvement? 30 min, 60 min, and at transfer to an inpatient unit with no difference J Am Coll Cardiol 2017;69(20):2542–50. https://doi.org/10.1016/j.jacc.2017.03.563. in adverse events when compared to IVP metoprolol. While this study is limited due to its size, available data is scarce and further studies are warranted in this specific population to validate safety and efficacy in the acute setting.