Arrhythmias vs. Coronary Artery Blockage: A Patient's Journey - Cardiology

Arrhythmia or coronary artery obstruction?

---

I do not smoke, am not obese, and have no family history of hypertension.
However, over the past two to three years, my cholesterol levels have gradually increased beyond the normal range, and my blood pressure has also slightly exceeded normal values.
I do not experience noticeable shortness of breath while walking to work, and my breathing calms down quickly after climbing four flights of stairs to my office.
In the past year or two, I have been waking up earlier in the morning, often startled by a pounding heart.
Occasionally, I feel pain in the blood vessels of my left arm.
(Recently, I noticed that the artery on the inner side of my left upper arm, where blood pressure is typically measured, feels noticeably thicker and more tortuous compared to the same area on the right arm, resembling distended veins.) I consulted a doctor who reviewed my electrocardiogram and prescribed Inderal (the purple one), but no further tests like echocardiography were conducted, and I was told everything seemed fine.
At the beginning of this lunar new year, while sitting on the couch watching TV, I distinctly felt my heart pounding, and I experienced intermittent discomfort between my left chest and ribs.
My wife noticed that I unconsciously rubbed my ribcage while sleeping.
In mid-February, I visited a cardiology clinic for an echocardiogram and a 24-hour Holter monitor (my first time).
The doctor mentioned that my heart muscle is thicker than normal, possibly due to hypertension (though I have never had long-term hypertension, at least I believe I do not).
I then underwent a myocardial perfusion scan (one scan in the morning after the injection, without exercise or treadmill, and another scan after lunch).
The doctor indicated that there might be signs of myocardial ischemia, possibly due to coronary artery blockage or thickened myocardium, and recommended a cardiac catheterization or a CT scan.
I was concerned about the invasiveness of the catheterization and asked for the doctor's opinion; he suggested the CT scan, which has an accuracy of up to 95%, so I opted to pay out of pocket for the scan.
(However, the doctor seemed to prefer the catheterization.) Later, I realized that the CT scan might be more harmful to the body.
The scan report indicated that the arterial blockage rate was <25%, suggesting no blockage, but the doctor still mentioned the possibility of coronary artery obstruction.
Previously, I took one tablet each of (1) cholesterol-lowering medication (Toren) and (2) heart medication (Concor) before bed.
However, I once felt as if my heart was relaxing too much and nearly stopping during a weekend night (it should not have been blocked), which made me uncomfortable enough to consider going to the emergency room.
(I still occasionally experience similar discomfort, and when I check my blood pressure and heart rate during these episodes, my heart rate is below 60, though not excessively low.
Could this be a side effect of the medication? Sometimes I feel a tightness in my throat, as if I have phlegm that I cannot cough up; could this also be a side effect?) The doctor suggested that I might be more sensitive to the medication and noted that my cholesterol had significantly decreased, so he reduced the dosage to half a tablet.
Concerned about potential issues at night, I changed my medication schedule to after lunch each day.
At the end of July, the doctor arranged for another echocardiogram and a second 24-hour Holter monitor.
He mentioned that I have mild arrhythmia (why was this not detected the first time?), and advised me to continue taking the medication, with a follow-up appointment in mid-October.
Now, I feel like I am back to square one; my discomfort has not improved and is no different from before my visit at the beginning of the year.
I am worried that the doctor has not identified the true underlying cause of my condition.
What should I do? (1) Continue taking the medication (I still experience a fast heart rate in the morning, discomfort between my ribs, and episodes where it feels like my heart is about to stop, although the frequency has decreased and the intensity is less severe), and wait to discuss this with the doctor in October, or (2) obtain my medical records and seek a second opinion from another hospital? (3) During this period of medication, I have lost about 5 kilograms; is this normal? Should I see a pulmonologist for the phlegm that I cannot cough up?

---

Fei, 50~59 year old female. Ask Date: 2016/08/08