Severe right coronary artery stenosis
Short Summary

49-year-old-male complained of a feeling of oppression behind the sternum, always when there was emotional stress. His coronary CT showed Severe high level stenosis with wall irregularities of the right coronary artery. The treatment options are coronary revascularization procedure versus optimized pharmacologic management.

Patient's Questions
1)    Is performance of a coronary angiogram indicated anyway to confirm the diagnosis and degree of stenosis?

2)    Regardless of the possible stability of the stenosis, not being able to identify a potentially unstable lesion at this time, considering the kind of work performed by the subject, who will be exposed to additional occasional stress, is surgical treatment advisable anyway?

3)    At the request of the patient in question, what are the risks (and with what percentages) correlated to the two strategic options: conservative with medical treatment or surgical treatment with angioplasty?
Medical Background

 49 years old, male

Diagnosis: Severe right coronary artery stenosis
 
The patient works in management for an Insurance Company.  
On March, after significant emotional stress in the office, the patient complained of a feeling of oppression behind the sternum that lasted approximately 20 minutes with high BP values (190/120 mmHg). The symptoms improved after taking sublingual Carvasin (isorbide dinitrate) and 1 tab Lasix with a progressive reduction of BP values.
An ECG was done at the ER of Santo Spirito Hospital in Rome, which showed non-specific inferior ST and V6 abnormalities, and an initial blood test for necrosis markers was negative.
The patient left the hospital of his own initiative and was hospitalized in the CICU (Coronary Intensive Care Unit) at Casa di Cura Mater Dei in Rome, where an ECG was performed comparable the previous one, Echocardiogram: no significant pathological conditions and a second blood test for necrosis markers which was again negative. Indications were given to perform a coronary CT scan, which the patient temporarily refused, releasing himself from the hospital.
After a discussion with his attending cardiologist, who confirmed the indications of the test, the patient underwent a 128-slice coronary CTwith contrast, which showed:
-           LMCA (Left main coronary artery) normal,
-           LAD (Left anterior descending artery): irregular calcified plaque immediately beyond the large diagonal branch (40% stenosis). The segment beyond is of regular size.
-           Cx(Circumflex artery): well developed, calcified wall irregularities, no stenosis.
-           RCA (Right coronary artery) strongly dominant. Severe high level stenosis, with wall irregularities, in the distal segment upstream of the crux.
From subsequent investigation of the case history, the patient revealed that other times, since about three years ago, in particularly taxing work circumstances, he has had a feeling of oppression behind the sternum, always when there was emotional stress, lasting less time and being less intense than that which occurred on March, which would spontaneously regress after the initiating emotional stress ended.
The patient, who suffers from high arterial blood pressure diagnosed 3 years ago, is in treatment with Zofenopril 30 mg + Doxazosin 4 mg with good control of BP levels (max 130/80 mmHg).
Family history of stroke and high arterial blood pressure. No other CV risk factors. ASA intolerance
He has periodic cardiovascular check-ups and exercises daily at medium-high intensity regulated with a heart rate monitor in relation to the max stress test heart rate (aerobic workout: floor exercise, aerobic exercise, step; anaerobic work-out: spinning). He has never had symptoms during sports activities.
At the time of a stress test performed in September 2005 (cycle ergometer, protocol 25 Watt increase every 2 min, Max HR 151 bpm, Theoretical max HR, total workload 200 Watt), without symptoms, mild ST segment depression in D2-D3-AVF and in V6 appeared 5 minutes into recovery.
For this reason, in October 2005 the patient underwent a 64-slice Cardio CT, with and without contrast, at the Policlinico Umberto 1 or Rome, which revealed:
-           normal CT,
-           LAD: dense calcified plaque in the middle second, immediately beyond the origin of D1, without significant blood vessel reductions.
-           CX: dense calcified plaque with an insignificant reduction of size.
-           RCA: dominant, regular size with dense fibrocalcific plaque at the distal third causing 30% stenosis.
In November 2005, myocardial scintigraphy was performed (201T 111 MBq EV9) with a stress test performed up to 82% of the max HR, with negative results for regional activity.
Last ergometric test performed on January 2009: cycle ergometer, maximal, 25 W increase every 2 min, HR 148 (86% of max theoretical HR), total workload of 200 W. Mild non-specific repolarization disturbances in V5-V6 3 minutes into recovery. Regular increase and decrease of BP. No symptoms.
Several echocardiograms were performed which did not reveal significant pathologies and ECG at rest that showed no alterations.
Currently asymptomatic with good cardiovascular compensation. BP 130/80 mmHg. SR HR 60 bpm.
Treatment followed:

 

Expert's Opinion

1)            Is performance of a coronary angiogram indicated anyway to confirm the diagnosis and degree of stenosis?
Although evidence-based cardiovascular medicine and contemporary guidelines certainly allows to continue treating this patient medically using pharmacotherapy alone, it is my bias in this case to consider a diagnostic coronary angiography and/or revascularization procedure (pending findings) due to the following arguments:
  • There have been some significant alarming symptomatic signs in this gentleman and I would suspect that he might sustain somewhat more severe coronary artery disease (CAD) in relation to the non-invasive cardiac findings.
  • It seems that between the year 2005 to 2009 there is an accelerated atherosclerotic course of the RCA disease. Rapid plaque expansion might be a surrogate morphological marker for "vulnerable plaque" and thus I would not want to wait for the "next symptomatic episode" which may be unpredictable in this patient.
  • This is an active, relatively young executive gentleman, and I would discuss with him the possibility of undergoing a coronary angiography for those aforementioned reasons. Nonetheless, I would present the matter to him in a balanced fashion (this is not a "black or white type of recommendation") with my tendency to recommend on elective coronary angiography over the next few weeks.
  • During the course of coronary angiogram, additional diagnostic measures could be undertaken in order to enhance the diagnostic capacity of the test. Those measures could include the performance of a coronary physiologic test (e.g. FFR=fractional flow reserve) and/or intra-coronary ultrasonic imaging (IVUS) if the angiographic findings are not conclusive about the need for revascularization. 
  • If indeed the patient would become a candidate for a percutaneous revascularization procedure, the fact he is allergic to aspirin plays a major and restrictive role here as it limits the percutaneous revascularization strategy towards optimized POBA (i.e. balloon or cutting balloon) or one of the new generation of bare metal stents (BMS) utilization. Due to the ASA allergy I would probably not consider to use a drug eluting tent (DES) in this case. Regardless, I would advise to better define the term "aspirin sensitive" in this case.
  • I am not aware of the patient's lipid profile and/or hs-CRP levels. Those measures should be drawn and I would probably recommend to initiating a statin management, using for example Crestor (Resuvastatin) @20 mg daily and pending on the LDL profile (aiming to get it down towards 70 mg/dl while monitoring potential enzymatic and/or clinical side-effects).
2)         Regardless of the possible stability of the stenosis, not being able to identify a potentially unstable lesion at this time, considering the kind of work performed by the subject, who will be exposed to additional occasional stress, is surgical treatment advisable anyway?
  • Cardiac CTA can not detect plaque stability thus I would not rely on this modality to conclude whether the plaque is stable or not. Nonetheless, as stated above, there is an indicator here for accelerated atherosclerotic course of the RCA disease which might indicate that the plaque is indeed "vulnerable or accelerated" but this is a speculative (albeit clinically relevant) conclusion.
  • Since the patient previously reported on exacerbation of angina secondary to emotional stress and accelerated hypertensive events, I would highly recommend on adding a beta blocker medication to his treatment. I would start with a selective β1 antagonist such as Bisoprolol Fumarate 2.5 mg/daily and monitor for heart rate and blood pressure.
  • Considering the term "surgical treatment", I presume it refers to a surgical coronary revascularization procedure (i.e. bypass surgery). I would advise first to establish a precise diagnosis and define the pathology during the course of a coronary angiography and only then to determine the appropriate revascularization strategy in this case.
3)         At the request of the patient in question, what are the risks (and with what percentages) correlated to the two strategic options: conservative with medical treatment or surgical treatment with angioplasty?
  • To the best of our current knowledge, the risk for cardiovascular mortality would not differ with the adoption of those 2 strategies (angioplasty vs. medical management), pending upon optimization of the medical management (e.g. statin and beta-blocker management as specified above).
  • The risk of myocardial infarction is unpredictable (probably in the range of 2-3%/year) and thus could not necessarily be altered in favor of one approach over the other.
  • The risk for accelerating angina might be better managed using angioplasty but this statement should be taken with cautious due to: 1) ambiguous coronary diagnosis so far, 2) need for an 'upgraded' medical (pharmacologic) management, 3) the fact that this patient has an unpredictable pattern of angina which is not too often and/or severe. Thus, optimized pharmacologic management is certainly a legitimate strategy here prior to adopting a more 'invasive' strategy.

 

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